bluuebunny/crossref_metadata_2025 huggingface dataset:
SEASONAL ADJUSTMENTS IN CAPTURED WILD NORWAY RATS: II. SURVIVAL TIME, PELT INSULATION, SHIVERING, AND METABOLIC AND PRESSOR RESPONSES TO NORADRENALINE
Authors: Héroux O. , Wright Donna
Published: December 2009

During the winter, wild rats (Rattus norwegicus) develop metabolic adjustments similar to those found in the white rats acclimated to cold in the laboratory. The rate of shivering found in the winter-captured wild rats is lower than that found in the summer-captured rats, indicating the presence of non-shivering thermogenesis. The metabolic response to noradrenaline is enhanced suggesting that non-shivering metabolism in these wild rats, as in the case of white rats, is mediated by noradrenaline. Unlike white rats acclimated to a constant cold temperature in the laboratory, but like white rats acclimatized to cold by group exposure to outdoor winter conditions, wild rats develop a greater pelt insulation in winter.
BIOSYNTHESIS OF THE COUMARINS: III. THE ROLE OF GLYCOSIDES IN THE FORMATION OF COUMARIN BY HIEROCHLOE ODORATA
Authors: Brown Stewart A.
Published: December 2009

Coumarinic acid β-glucoside has been identified in Hierochloe odorata. Carbon dioxide-C14was administered to this species, and the plants were allowed to metabolize for periods up to 31 days. "Free" coumarin was recovered by simple extraction, and additional coumarin and o-coumaric acid were recovered after hydrolysis of the corresponding glucosides with emulsin. The total C14in o-coumaric acid reached a maximum in about 4 days and then declined, but the peak in the total C14of coumarin was not reached until 8 to 17 days after activation. o-Coumaryl glucoside and coumarin are thus both metabolic intermediates rather than end products, and the glucoside is formed first. This supports the orthohydroxylation theory of coumarin biosynthesis. The specific activity of coumarin liberated by emulsin hydrolysis from the glucoside was consistently lower than that of "free" coumarin. This is irreconcilable with the proposed formation of free coumarin from coumarinic acid glucoside as a major pathway in vivo unless separate pools of the glucoside exist in the plant. Indirect evidence is presented that free coumarin can exist in Hierochloe.
KINETIC FORMULATIONS FOR ENZYMIC REACTIONS INVOLVING TWO SUBSTRATES
Authors: Wong J. Tze-Fei , Hanes Charles S.
Published: December 2009

The general mechanism for enzymic group-transfer reactions is shown to be of considerable complexity. In order to deal with this complexity, an analysis has been made of the structure of steady-state rate equations, which permits the establishment of direct relationships between specified features of mechanism and of rate behavior. This has opened up the possibility of a featurewise approach for the progressive elucidation of complex enzymic mechanisms. In particular, a theoretical basis has been provided for the comprehensive consideration and systematic differentiation of mechanisms of enzymic group-transfer reactions.
PATHWAYS OF CARBOHYDRATE METABOLISM IN LOBSTER HEPATOPANCREAS
Authors: Hochachka P. W. , Teal J. M. , Telford M.
Published: December 2009

Oxygen uptake by homogenates of lobster hepatopancreas was stimulated by the addition of Embden–Meyerhof, pentose cycle, and citric acid cycle intermediates as well as xylose. Acetate-1-C14oxidation was blocked by fluoracetate and glucose-1-C14oxidation fell by 80% with iodoacetate treatment. TPN and DPN increased glucose-1-C14oxidation by 140% and 20% and acetate-1-C14oxidation by 50% and 100% respectively. Large amounts of C14enter polysaccharide following treatment with glucose-1-C14or acetate-1-C14but very little enters after treatment with the same amount of gluconate-1-C14. Gluconate and xylose oxidation occurs in mitochondria-free preparations. In short-term tests with acetate-1-C14as substrate, most of the label in glycogen is on carbons 3 and 4 and the amount in the other positions can be explained on the basis of a 5–10% participation of the pentose cycle.
LIPID SYNTHESIS IN RAT LIVER PARTICLES: DIVERSION OF SYNTHESIS FROM TRIGLYCERIDE TO LECITHIN BY THE IN VITRO ADDITION OF CYTIDINE DIPHOSPHATE CHOLINE
Authors: Strickland K. P. , Rossiter R. J.
Published: December 2009

When particle preparations from rat or chicken liver were incubated in a suitable medium containing α-glycerophosphate-C14, radioactivity was recovered from lecithin, phosphatidyl inositol, phosphatidic acid, and triglyceride. Whole homogenate and various particle preparations catalyzed the dephosphorylation of a number of phosphatidic acids, with the liberation of inorganic P.It is currently believed that liver preparations are capable of catalyzing the esterification of L-α-glycerophosphate, with the formation of L-α-phosphatidic acid, which subsequently may be dephosphorylated to form D-α,β-diglyceride. The diglyceride so formed may then give rise either to lecithin, by combining with phosphorylcholine from cytidine diphosphate choline, or to triglyceride, by combining with fatty acid from fatty acyl coenzyme A. If these reactions occur in liver particle preparations, it should be possible, by the addition in vitro of unlabelled cytidine diphosphate choline, to divert the synthesis of lipid from the formation of triglyceride to the formation of lecithin. In experiments designed to put this hypothesis to the experimental test, such a diversion of lipid synthesis was achieved.
STUDIES ON THE MECHANISMS BY WHICH ERUCIC ACID AFFECTS CHOLESTEROL METABOLISM: DISTRIBUTION OF ERUCIC ACID IN ADRENAL AND PLASMA LIPIDS
Authors: Carroll K. K.
Published: December 2009

The effect of dietary erucic acid on the fatty acid composition of cholesterol ester, triglyceride and phospholipid fractions of rat adrenal, and plasma has been determined. Lipid classes were separated by chromatography on Florisil and their component fatty acids were determined by gas–liquid chromatography. Erucic acid was found in large amounts in adrenal cholesterol esters and in moderate amounts in adrenal and plasma triglycerides. Only small amounts were found in plasma cholesterol esters or the phospholipids of either adrenals or plasma. Eicosenoic acid was observed in some cases and the level of oleic acid was increased in most lipid classes of both tissues. This indicated partial stepwise oxidation of erucic acid. The increase in adrenal cholesterol caused by feeding erucic acid appears to be due primarily to accumulation of cholesterol erucate.
EFFECTS OF SECTION OF THE CORPUS CALLOSUM ON DECOMPRESSION HYPOXIA AND ON PENTYLENETETRAZOL (METRAZOL) CONVULSIONS
Authors: Manax S. J. , Stavraky G. W.
Published: December 2009

Electroencephalographic studies were carried out in white rats with chronically implanted electrodes located on the skull over the frontal areas of the brain, with the animals suspended in a sling in a decompression chamber. Exposed to simulated elevated altitude at weekly intervals 4 to 6 months after section of the corpus callosum 26 animals revealed a greater sensitivity to hypoxia than 22 controls. This was shown by a lower threshold of convulsibility and by a longer duration of the convulsions. Under the experimental conditions employed the electrocortical activity in control animals consisted of 1.5–3 c/s and 4–6 c/s waves of up to 40-μv amplitude with 11–14 c/s waves superimposed. In the corpus-callotomized rats the activity was somewhat slower and of a higher amplitude, this being more apparent [Formula: see text] months after the operation than at the time of the decompression experiments. Decompression of both groups of animals resulted in characteristic EEG changes culminating in the appearance of hypoxic preconvulsive potentials of high voltage (60–180 μv) and slow frequency (1.5–3 c/s) which were first grouped in paroxysms of about 3 to 5 seconds' duration, later becoming continuous. When decompression was continued, this activity was followed by convulsive discharges, all of the manifestations being more pronounced and recurring at lower altitudes in the corpus-callotomized animals than in the controls. An analysis of the wave patterns in 28 sacrifice experiments with transection of the spinal cord and curarization of the animals showed that the observed EEG activity did not depend on motor components.The EEG patterns during the excitatory stages of hypoxia or asphyxia resembled closely certain phases of pentylenetetrazol-induced activity; however, at the height of the convulsive EEG pattern induced by pentylenetetrazol, periods of asphyxia disorganized the spike activity caused by this agent and markedly depressed the EEG.
EFFECT OF COLD ON RATS CHRONICALLY EXPOSED TO MALATHION
Authors: Marton A. V. , Sellers E. A. , Kalow W.
Published: December 2009

Wistar rats received 4000 p.p.m. of malathion in their daily diet without showing evidence of intoxication (normal appearance, growth, food intake). When the animals were clipped and exposed to an ambient temperature of 1.5 °C they survived for a much shorter period in the cold environment than did control animals not receiving malathion. In both experimental and control groups, deaths occurred when body temperatures had dropped to about 18 °C. During the initial period in the cold environment, animals of both groups were able to increase their oxygen consumption to the same extent. There was no indication of an increased heat loss by the malathion-treated rats. It thus appeared likely that the insecticide decreased the ability of rats to produce heat continuously over a prolonged period at a high rate. The activities of cholinesterase in plasma were reduced in the malathion-treated rats but were not affected by the cold stress.
STUDIES ON THE FORMATION OFD-ARABITOL BY OSMOPHILIC YEASTS
Authors: Blakley E. R. , Spencer J. F. T.
Published: December 2009

The formation of D-arabitol by a strain of osmophilic yeast has been studied. Both D-ribulose and D-xylulose were good substrates for the respiration of yeast, but D-xylulose was a better growth substrate than D-ribulose and produced larger amounts of D-arabitol. The utilization of D-xylulose-5-C14by the yeast resulted in the production of D-arabitol having two-thirds of the radioactivity in carbon-1. Extracts of the yeast contain an enzyme system which reduces D-xylulose to arabitol in the presence of NADH. The enzymatic activity increases with decreasing pH to 4.5, but the activity is readily destroyed below pH 7. The data presented suggests that D-xylulose is a precursor in the formation of D-arabitol by the osmophilic yeast.
THE PREPARATION AND PROPERTIES OF 20α-DIHYDROCORTICOSTERONE
Authors: Darrach Marvin , Krehbiel Ruth
Published: December 2009

The preparation of 20α-dihydrocorticosterone chemically and enzymatically is described, proof of structure is given, and the physical properties of 20α-dihydrocorticosterone and its 20α,21-diacetate are recorded.
BICARBONATE EXCRETION DURING HYPOTHERMIA
Authors: Kanter G. S. , Lubinski R. H. , Mielens I. M.
Published: December 2009

The investigation was designed to determine whether the renal loss of bicarbonate contributes significantly to the acidosis of hypothermia. The excretion of bicarbonate during hypothermia was studied in five infused (6% creatinine in saline at 0.4 ml/minute) and five non-infused dogs. All animals were anesthetized and artificial respiration was not used. The rectal temperature was gradually reduced to the 26–27 °C range by approximately 4 hours of exposure to ice packing. After control, clearance periods of 30 minutes' duration were conducted serially and continually through the experiment. There was no significant increase in bicarbonate excretion during hypothermia in the non-infused group. The urinary pH remained at control levels of about 6.2. The fall in arterial pH was not due to urinary bicarbonate loss. The urinary pH in the infused group, which had a higher urine flow, increased to pH 6.7 due to increased excretion of bicarbonate. The urine pH in three animals with highest urine flows in this latter group approached plasma levels. The excretion rate of bicarbonate in the infused group, however, was similarly insufficient to account for the decrease in arterial pH. The hypothermic kidney is quite effective in reabsorbing bicarbonate.
THE ABSENCE OF THIAMINE PHOSPHATES FROM CEREALS
Authors: Sen N. P. , Robinson A. D.
Published: December 2009

A method was devised for the separation and estimation of thiamine and its mono- and di-phosphates in cereals by extraction with perchloric acid, separation on a column of Decalso, elution with a strong solution of potassium chloride, and anion exchange chromatography with Dowex-1. Estimation was based on the thiochrome method with and without prior enzymic digestion. Analyses of two varieties of each of stored wheat, barley, and oats showed that each contained both free and bound thiamine but that none of the latter was in the form of phosphates.
THE INFLUENCE OF pH ON THE ACTIVITY OF NICOTINE AT THE NEUROMUSCULAR JUNCTION
Authors: Hamilton John T.
Published: December 2009

The effects of pH on the activity of nicotine relative to that of nicotine monomethiodide have been studied on the frog rectus abdominis preparation. Results have been obtained which substantiate the view that it is the univalent nicotinium ion, rather than the un-ionized base, which acts at the neuromuscular junction.
SERIAL DETERMINATIONS OF EXTRACELLULAR FLUID VOLUME USING THE RADIOSULPHATE SPACE METHOD
Authors: Murphy Beverley , Dossetor J. B. , Beck J. C.
Published: December 2009

The fate of injected and ingested radiosulphate was investigated. The appearance of radiosulphate in bile was shown to be very rapid. Ingested radiosulphate was rapidly and completely absorbed, peak blood levels occurring at 1 to 2 hours.The sulphate space method of measuring extracellular fluid volume was studied and a method adopted requiring two serum samples taken at 1/2 and 6 hours following injection. This procedure provided a convenient means of making independent observations of extracellular fluid volume as often as four times a day in individual subjects. When values for the sulphate space were compared in the same individuals under conditions similar with respect to diet, activity, and time of day, the coefficient of variation was calculated to be ± 5.7% or about ± 1% of body weight. Values among well-nourished subjects with no known abnormalities of water or electrolyte balance gave a mean of 17.5% body weight with a range of 13.5 to 22% body weight. Values among obese subjects averaged 12.8% body weight.Studies of the diurnal variation of the sulphate space made every 6 hours throughout the day suggested that in man, under conditions of uniform intake and normal activity, there is a diurnal variation of extracellular fluid volume, higher values occurring at night.
ON THE HYPERTENSIVE ACTION OF TOLAZOLINE AND HYDERGINE
Authors: Benfey B. G. , Varma D. R.
Published: December 2009

The effects of tolazoline and Hydergine on blood pressure, cardiac contractility, and heart rate have been studied in dogs under pentobarbitone anesthesia. Whereas in the absence of reserpine, tolazoline had a pressor effect in two of four dogs, following reserpine it had a marked pressor action in each of eight dogs. The blood pressure rise was associated with positive inotropic and negative chronotropic effects. Phenoxybenzamine abolished these effects of tolazoline. Hydergine had pressor and negative chronotropic effects in the absence of reserpine. Following reserpine these effects were associated with positive inotropic actions. Phenoxybenzamine reduced these effects of Hydergine. It is concluded that the pressor action of tolazoline is wholly due to adrenergic vasoconstriction, whereas that of Hydergine is only partly an adrenergic effect.
NORADRENALINE AND SURVIVAL OF RATS IN A COLD ENVIRONMENT
Authors: Schönbaum E. , Sellers E. A. , Johnson G. E.
Published: December 2009

There is evidence that noradrenaline is implicated in the non-shivering thermogenesis of cold-acclimated rats, and that it may be concerned with thermogenesis of normal non-acclimated animals. The effects of noradrenaline on rats exposed to cold acutely or on rats acclimated to cold were studied. Moderate to large doses of noradrenaline produce hypothermia that frequently terminates lethally in rats acclimated to 23 °C and acutely exposed to cold (2 °C), but not in cold (2 °C) acclimated rats nor in 23 °C acclimated rats kept at that temperature. The LD50of noradrenaline (i.p.) in mice kept at 30 °C is 7.37 mg/kg, but in mice acutely exposed to 2 °C the LD50is 3.66 mg/kg. A large dose (500 μg/rat) of noradrenaline inhibits shivering in acutely cold-exposed rats and reduces the oxygen consumption. The same dose stimulates oxygen consumption in cold-acclimated rats. Rats living at 2 °C, treated chronically with guanethidine or reserpine in order to reduce tissue levels of noradrenaline, became acclimated to 2 °C (as shown by an increased resistance to cold exposure, and the presence of non-shivering thermogenesis). It is concluded that the presence of increased amounts of noradrenaline in tissues or in circulation is not required for the occurrence of acclimation to cold.
A METHOD FOR AUTOMATICALLY MAINTAINING THE BODY TEMPERATURE OF RATS AT A CONSTANT LEVEL
Authors: Ashworth M. A. , Haist R. E.
Published: December 2009

A method is described for continuously and automatically regulating the body temperature at lower than normal levels in up to 12 rats at one time.
A MULTIPLE-COLUMN HYDRAULIC METHOD FOR FRACTIONATION OF PARTICLES FOR CHROMATOGRAPHIC COLUMNS
Authors: Whitaker D. R. , Strasdine G. A.
Published: December 2009

An apparatus for fractionation of particles is described. Liquid at constant temperature is freed of air bubbles and circulated at constant flow rate through a series of vertical columns of progressively increasing diameters, a settling bottle, and a filter. The particles to be fractionated are either added gradually to the first column by passage of the return flow of liquid through a particle reservoir or are added at the outset to the first column. The flow of liquid distributes the particles between the columns according to particle size and density. Illustrative data are given for fractionation of a cross-linked dextran, a diatomaceous earth, a microbead ion-exchange resin, and a micropowder ion-exchange resin.
GLYCYL-RNA SYNTHETASE OF RAT LIVER: PARTIAL PURIFICATION AND EFFECTS OF SOME METAL IONS ON ITS ACTIVITY
Authors: Fraser M. J.
Published: December 2009

Glycyl-RNA synthetase has been purified 40-fold from a 105,000 × g supernatant of an homogenate of rat liver by successive precipitation at pH = 5.0, heat treatment at 55 °C for 3.0 minutes in the presence of 1.0 mM ATP, and ammonium sulphate fractionation. The purified fractions catalyzed glycine-dependent ATP-32PP exchange. The effect of some metal ions on glycine activation was studied. Activation occurred in the presence of either Mg++or Mn++. The apparent stimulation of glycine activation by Co++was found to be an artifact.
SEPARATION OF BOVINE LENS CARBONIC ANHYDRASE INTO TWO COMPONENTS
Authors: Sen Mira , Drance S. M. , Woodford V. R.
Published: December 2009

Two components of carbonic anhydrase have been separated in partially purified forms from the soluble proteins of bovine lens. During the chromatographic separation on diethylaminoethyl cellulose columns, the total carbonic anhydrase increased, on an average, by nine times. The implications of these findings are that bovine lens carbonic anhydrase may exist in the form of two isoenzymes and that there may be a naturally occurring in vivo inhibitory mechanism regulating the activity of bovine lens carbonic anhydrase in situ.
STUDIES OF THE CATIONIC, AND ACETYLCHOLINE, STIMULATION OF PHOSPHATE INCORPORATION INTO PHOSPHOLIPIDS IN RAT BRAIN CORTEX IN VITRO
Authors: Brossard Maurice , Quastel J. H.
Published: December 2009

The addition of 0.1 M KCl to, or the omission of CaCl2from, incubation media in which rat brain cortex slices are respiring, stimulates the incorporation of inorganic P32into phospholipids. It also stimulates the labelling of 7-minute hydrolyzable nucleotide phosphates, but decreases their levels. The stimulation of P32incorporation into total phospholipid takes place primarily into phosphatidic acid and phosphoinositide but not into phosphatidyl choline and phosphatidyl ethanolamine. The addition of succinate and γ-aminobutyrate to brain cortex slices, metabolizing glucose, markedly inhibits the labelling of phospholipids although the respiration of slices is not diminished. The potassium stimulation of phospholipid labelling only occurs if sodium ions are present in the incubation medium. The lesser stimulation due to absence of calcium ions seems, however, to be independent of the presence of sodium ions. Acetylcholine stimulation of P32incorporation into phospholipids is dependent on the presence of sodium ions. Such stimulations are suppressed by concentrations of malonate, iodoacetate, fluoride, and ethanol that have little effect on the unstimulated incorporation of P32. Atropine and hyoscine inhibit acetylcholine stimulation but not cationic stimulation of P32incorporation. It is suggested that the effect of acetylcholine on P32incorporation is mediated by cationic changes at the nerve cell membrane.
THE EFFECT OF THYROID ADMINISTRATION ON THE PANCREATIC AMYLASE ACTIVITY OF HYPOPHYSECTOMIZED AND INTACT RATS
Authors: Maykut Madelaine O. , Nishikawara Margaret T. , Haist R. E.
Published: December 2009

The administration of desiccated thyroid gland to hypophysectomized rats prevented the marked atrophy of the pancreas which was consistently observed following hypophysectomy. Thyroid feeding at two dose levels led to a significant increase in the pancreatic amylase activity of hypophysectomized rats. This held whether the results were expressed as total activity or were given as activity per unit of body weight, per unit of pancreas, or per mg nitrogen. Except for the activity per unit of body weight, the amylase activity of the thyroid-treated hypophysectomized rats was significantly lower than the amylase activity in untreated, intact controls. In the thyroid-fed, hypophysectomized rats the amylase activity per unit of body weight was not significantly different from that of intact, untreated controls.Thyroid administration in intact rats resulted in a decrease in the pancreatic amylase activity.
EFFECT OF IONIZING RADIATION ON THE PYRIDINE NUCLEOTIDES OF THYMOCYTES
Authors: Scaife J. F.
Published: December 2009

The pyridine nucleotides of thymocytes have been examined following irradiation of the cells in vivo or in vitro. NAD was found to constitute about 95% of the total oxidized pyridine nucleotides in thymocytes while the level of NADH2was found to be very low. There is a rapid loss of NAD from thymocytes following irradiation in vitro or in vivo which is evident with as little as 25 rads. There is no concomitant rise in the NADH2levels following irradiation. The loss of NAD occurs principally from the nucleus of the cell and is characterized by an intracellular release of NADase from the mitochondria and nucleus into the cytoplasm. Following irradiation there is a reduced capacity for thymocytes to synthesize NAD from 7-C14-nicotinamide either in vitro or in vivo. The administration or presence of nicotinamide produces an unphysiological increase in the level of NAD in whole thymus or thymocytes in suspension. The level of NAD in treated cells is higher than in untreated controls following irradiation. This effect is not produced by nicotinic acid, cysteamine, L-cysteine, or promethazine. The administration of nicotinamide does not prevent the development of pyknotic degeneration in irradiated thymocytes. There is no change in the RNA content of the thymus under the conditions which reduce the NAD content.
ORGANIC ACIDS OF BRYOPHYLLUM CALYCINUM THE ISOLATION OF MONOPOTASSIUM ISOCITRIC LACTONE
Authors: Wilson D. G.
Published: December 2009

A method is described for the isolation from dried Bryophyllum calycinum leaf tissue of threo-Ds-isocitric acid as the monopotassium salt of the lactone. Overall yields of 49 to 62% of the isocitric acid in the organic acid extract were obtained. Some of the properties of this salt are described.The preparation of (−)-isocitric acid lactone, and of the monoammonium, monorubidium, and lithium salts of the lactone is also described.
THE EFFECT OF 4-METHYLTROPOLONE ON THE METABOLISM OF ADRENALINE
Authors: Mavrides C. , Missala K. , D'Iorio A.
Published: December 2009

The inhibiting effects of 4-methyltropolone have been tested in a partially purified preparation of O-methyltransferase from rat liver. The inhibition observed was of a strictly competitive nature whether the enzyme was or was not preincubated with the inhibitor. Addition of the substrate partially reversed the inhibition.The injection of C14-labelled adrenaline in rats pretreated with 4-methyltropolone (30 mg/kg) clearly indicated a decreased excretion of labelled metanephrine.
BODY ORGAN CYTOCHROME OXIDASE ACTIVITY IN COLD- AND WARM-ACCLIMATED RATS
Authors: Janský Ladislav
Published: December 2009

The cytochrome oxidase activity was estimated in homogenates of the whole body and in nine body organs of cold- and warm-acclimated rats. The total body cytochrome oxidase activity expressed in terms of oxygen consumption was similar in cold- and warm-acclimated rats. In cold-acclimated animals the total cytochrome oxidase activity did not differ from maximal steady state metabolism measured in vivo, while in warm-acclimated rats the total cytochrome oxidase activity was almost twice as great as the maximal steady state metabolism. The results indicate that warm-acclimated rats do not utilize the full capacity of the cytochrome system and that cold-acclimation makes full exploitation of the oxidase capacity possible. In cold-acclimated rats the cytochrome oxidase activity of the muscles comprised 57% of the total, the liver 22.5%, and the skin 6%, with smaller roles for other organs. The role of the liver was greater in cold-acclimated than in warm-acclimated rats.
SOME OBSERVATIONS ON THE PANCREATIC AMYLASE AND INTESTINAL MALTASE OF THE CHICK
Authors: Laws B. M. , Moore J. H.
Published: December 2009

The digestive enzymes amylase and maltase were studied in acetone-dried powders or homogenates of the pancreatic and small intestinal tissues and small intestinal contents obtained from chicks of various ages. The stability of pancreatic amylase, which was relatively low in 0.15 M sodium chloride, was increased markedly by the presence of 0.02 M barbiturate buffer. The pH optimum of pancreatic amylase (chloride-activated) was 7.0 whereas that of intestinal maltase was 6.9. High levels of pancreatic amylase activity were found in the newly-hatched chick but these levels decreased during the following 20 days and then remained constant. The contrast between the high amylase and low maltase activities in the contents of the small intestine suggested that molecules of maltose, formed by the hydrolysis of starch, were absorbed as such by the mucosal cells. It appeared that maltose could be absorbed with equal facility from all sections of the small intestine of the 10-day-old chick but in the older birds maltose absorption seemed to occur more readily from the upper small intestine than from the duodenum and lower small intestine. A modified method for the determination of maltase activity is described.
THE EFFECT OF ETHANOL ON THE METABOLIC RATE OF RATS
Authors: Kalant H. , Hawkins R. D. , Watkin G. S.
Published: December 2009

Alcohol injected intraperitoneally in a dose of 0.4 g/kg causes a small but significant elevation in the metabolic rate of anaesthetized rats. This effect appears to be masked in unanaesthetized rats, particularly with larger doses, presumably because of the sedative effect of the ethanol. Pretreatment with iproniazid (100 mg/kg) or phenoxybenzamine (10 mg/kg) failed to enhance or to block, respectively, the initial elevation in oxygen consumption induced by ethanol. These results suggest that the initial increase in oxygen consumption is brought about by some mechanism other than the release of adrenaline or of noradrenaline. Calculations suggest that this increase could be accounted for by preferential oxidation of ethanol in place of its caloric equivalent as glucose.
TOBACCO POLYPHENOLS: III. THE ROLE OF FERULIC ACID IN THE BIOSYNTHESIS OF CHLOROGENIC ACID
Authors: Runeckles V. C.
Published: December 2009

C14-labelled ferulic acid (3-methoxy-4-hydroxycinnamic acid) is actively metabolized by leaf tissues of Nicotiana tabacum with the formation of its glucoside and glucose ester, and the coumarin glucoside, scopolin (6-methoxy-7-O-β-D-glucosido-coumarin). There is considerably less utilization in quinic acid ester formation. The only quinic acid esters which become labelled following the administration of labelled ferulic acid in the light yield ferulic acid on hydrolysis. One of these is 3-O-feruloyl-quinic acid. In the dark, the principal quinic acid esters synthesized again contain ferulic acid, but a low incorporation of activity into chlorogenic acid (3-O-caffeoyl-quinic acid) can be demonstrated. These findings are discussed in relation to reports of the utilization of ferulic acid in chlorogenic acid biosynthesis in other higher plant tissues.
EFFECT OF DEUTECTOMY ON LEVELS OF BLOOD AND LIVER CHOLESTEROL AND ON THE INCORPORATION OF ACETATE AND MEVALONATE INTO LIVER CHOLESTEROL BY THE CHICK
Authors: Lupien P. J. , Migicovsky B. B.
Published: December 2009

The serum cholesterol level and the degree of incorporation of C14-acetate and C14-mevalonate into liver cholesterol has been studied in normal and deutectomized chicks.Serum and liver cholesterol levels in normal chicks decreased rapidly between 3 days and 5 days after hatching, and at 9 days of age the quantity of cholesterol stabilized at levels comparable to those of mature birds.Deutectomy significantly lowered serum cholesterol levels of the 5-day-old chicks but did not affect liver cholesterol levels.High levels of liver cholesterol in the 3-day-old chicks did not totally depress C14-acetate incorporation. Minimal C14-acetate incorporation was obtained when the chicks were 5 days of age and maximal incorporation occurred on the 15th day following hatching. C14-mevalonate incorporation into liver cholesterol was observed to be minimal when the chicks were 3 days of age and maximal when the chicks were 12 days of age.It is suggested that the chick might prove to be of value for the study of the control mechanisms in cholesterol metabolism.
GAS CHROMATOGRAPHIC FRACTIONATION OF NATURAL STERYL ESTER MIXTURES
Authors: Kuksis A.
Published: December 2009

Synthetic and naturally occurring mixtures of fatty acid esters of cholesterol and plant sterols were separated by gas chromatography under the conditions previously described for triglyceride fractionation. The separations obtained were based primarily on the molecular weight or carbon number of the material, a difference of one methylene unit either in the fatty acid or the sterol side chain being usually sufficient for a complete resolution. Under isothermal conditions, however, partial separations could also be brought about between certain esters differing only in the unsaturation of the fatty acid moiety. Using weighed mixtures of synthetic steryl esters proportionally correct quantitative recoveries were demonstrated for both cholesterol and plant sterol esters of the common fatty acids.
THE SEPARATION, DETERMINATION, AND CHARACTERIZATION OF 2-AMINO-2-DEOXY-D-GLUCOSE (D-GLUCOSAMINE) AND 2-AMINO-2-DEOXY-D-GALACTOSE (D-GALACTOSAMINE) IN BIOLOGICAL MATERIALS BY GAS–LIQUID PARTITION CHROMATOGRAPHY
Authors: Perry M. B.
Published: December 2009

A method for the separation, determination, and characterization of 2-amino-2-deoxy-D-glucose (D-glucosamine) and 2-amino-2-deoxy-D-galactose (D-galactosamine) is presented. Treatment of 2-acetamido-2-deoxy-α-D-glucose and 2-acetamido-2-deoxy-α-D-galactose in pyridine solution with trimethylchlorosilane and hexamethyldisilazane results in a rapid conversion of the glycoses to their respective trimethylsilyl 3,4,6-tri-O-trimethylsilyl-2-acetamido-2-deoxy-α-D-glycosides which are sufficiently stable and volatile to allow their separation and quantitative analysis to be made by gas–liquid partition chromatography. The two trimethylsilyl derivatives, collected by preparative gas–liquid partition chromatography, were crystalline compounds which had sharp melting points and characteristic infrared spectra and specific optical rotations. Quantitative analyses of mixtures of 2-amino-2-deoxy-D-glucose hydrochloride and 2-amino-2-deoxy-D-galactose hydrochloride were made by gas chromatographic analysis of their trimethylsilyl derivatives formed after prior conversion to their N-acetyl derivatives.The analytical procedure was applied to the characterization of 2-amino-2-deoxy-D-glucose in hyaluronic acid and 2-amino-2-deoxy-D-galactose in chondroitin sulphate. The quantitative procedure was also successfully applied to the analysis of mixtures of hyaluronic acid and chrondroitin sulphate by the gas–liquid partition chromatographic determination of the 2-amino-2-deoxy-D-glucose and 2-amino-2-deoxy-D-galactose in the hydrolyzates prepared from synthetic mixtures of the two mucopolysaccharides.
CHROMATOGRAPHIC BEHAVIOR OF HISTONES ON SEPHADEX AND CARBOXYMETHYLCELLULOSE
Authors: Johnson L. D. , Driedger A. , Marko A. M.
Published: December 2009

The chromatographic behavior of calf thymus histone on different grades of Sephadex with varying degrees of cross-linkages has been studied. Fractions of histone obtained by preliminary separation on carboxymethylcellulose were characterized by chromatography on Sephadex and by electrophoresis on gels of starch and polyacrylamide. Analytical separation on Sephadex has confirmed the ease of fractionation of histones by acid extraction.
ISOLATION OF CRYSTALLINE 16-EPIESTRIOL FROM HEN URINE
Authors: Hertelendy F. , Common R. H.
Published: December 2009

16-Epiestriol has been isolated in crystalline form from hen urine and characterized on the basis of the melting points of the isolated product and of two of its derivatives (acetonide, triacetate) and on the chromatographic behavior of the isolated product and five of its derivatives in each of three different solvent systems.
METABOLISM OF 6-MERCAPTOPURINE RIBONUCLEOSIDE BY EHRLICH ASCITES CARCINOMA CELLS
Authors: Paterson A. R. P. , Sutherland Aiko
Published: December 2009

Ribonucleoside derivatives of 6-mercaptopurine (6-MP) and other purine bases were rapidly catabolized when incubated with Ehrlich ascites carcinoma cells in vitro. The catabolism of purine ribonucleosides proceeded by way of phosphorolytic cleavage of the glycosidic linkage and resulted in accumulation of the liberated base in the incubation medium. The ribosyl portions of ribonucleoside substrates were utilized with the formation of lactate, which also appeared extracellularly.Cells of a 6-MP-resistant subline of the Ehrlich ascites tumor degraded 6-MP ribonucleoside (6-MPR) at rates comparable to those of the parent line. This finding, when considered with other characteristics of the resistant line of cells, implied that cleavage of 6-MPR took place in a cell compartment from which inosinate pyrophosphorylase was absent.
THE DEPOSITION OF LINOLEIC ACID IN RATS FED CORN OIL
Authors: Beare Joyce L. , Kates Morris
Published: December 2009

Rats were fed different levels (0–30%) of corn oil in a purified basal diet, and the proportion of linoleic acid in the total fatty acids of carcass and liver lipids measured by gas–liquid chromatography. At 9 weeks, the proportion of linoleic acid in the carcass fatty acids of rats receiving no fat was 2%, whereas in those receiving 20% corn oil the proportion was 46%; this level was not exceeded when 30% corn oil was fed for the same time. In rats fed 2 or 20% corn oil for intervals up to 24 days, the proportion of linoleic acid in the liver fatty acids reached a maximum more quickly than did that in the carcass. The concentration of linoleic acid in chromatographically separated liver neutral lipid, phosphatidyl choline, and phosphatidyl ethanolamine was influenced to different degrees by the dietary level of that acid. The greatest increase in linoleic acid occurred within 3 days in the liver neutral lipids of rats supplied with the higher level of linoleate; smaller increases occurred in the phosphatidyl choline within 3 days and in phosphatidyl ethanolamine within 6 days. With increasing levels of corn oil in the diet, the concentration of linoleic acid in the liver neutral lipids approached that of the dietary oil.
PHYSICOCHEMICAL PROPERTIES OF GLUTEN FROM THREE TYPES OF WHEAT
Authors: Matsuo R. R. , McCalla A. G.
Published: December 2009

Gluten dispersed in 8% sodium salicylate and in lactic acid – sodium chloride solutions yielded intrinsic viscosity values in decreasing order, hard, soft, and durum wheats. Dispersions prepared under nitrogen yielded higher values than those prepared in air. Treatment of gluten with performic acid or with large excesses of sodium sulphite reduced the intrinsic viscosity of all glutens but the order of the values remained the same. Sedimentation coefficients were significantly reduced by the treatments, with the greatest reduction for gluten from durum wheat treated with performic acid. Sulphydryl group analysis gave the lowest value for gluten from hard wheat and the highest for that from durum. Results suggest that disulphide and sulphydryl groups are involved in determining physicochemical properties of gluten.No significant differences among the glutens from the three wheats were found in sedimentation coefficients, in distribution of such coefficients, or in amino acid composition, nor in the diffusion constants or molecular weights for the most soluble fraction from each.
PROPERTIES AND CLASSIFICATION OF THE SOLUBLE ESTERASES OF HUMAN SKELETAL AND SMOOTH MUSCLE
Authors: Ecobichon D. J. , Kalow W.
Published: December 2009

Water-soluble proteins and enzymes of human skeletal and smooth muscle were separated by vertical-zone electrophoresis in starch gel and compared with those of human liver and kidney. Thirteen bands of proteins were detected with amido black in skeletal muscle, five of which were also detected in smooth muscle. Various substrates and inhibitors were used in efforts to identify enzymes. Ten bands of esterase activity were detected in skeletal muscle, and nine in smooth muscle. One zone, characteristic of serum cholinesterase, was believed to be due to serum contained in the tissue. A zone of isozymic esterases found in skeletal and smooth muscle was similar to a zone in human liver and kidney and reacted like an acetylesterase. Other esterase bands, which showed a marked hydrolysis of α-naphthyl butyrate, were similar to aliesterases of renal tissue. Observations on alkaline phosphatase, acid phosphatase, aminopeptidase, lactate dehydrogenase, and catalase were recorded for comparison with the data on esterases.
A COLORIMETRIC METHOD FOR SERUM CHYMOTRYPSIN DETERMINATION
Authors: Kallos J. , Arthur E. L. , Rizok D. , Kahn D.
Published: December 2009

A colorimetric method for serum chymotrypsin determination is presented. A specific substrate, N-acetyl-L-tyrosine hydrazide, is hydrolyzed by chymotrypsin, liberating hydrazine. This hydrazine is determined colorimetrically with Ehrlich's reagent. The procedure is suitable for the routine assay of serum chymotrypsin and its inhibitors.
THE EFFECT OF HOMOGENIZATION ON FREE AND ESTERIFIED FATTY ACID POOLS IN ADIPOSE TISSUE
Authors: Rubinstein David , Daniel Anna M. , Chiu Sylvester , Beck John C.
Published: December 2009

The effect of homogenization of adipose tissue on fatty acid pools was studied with palmitate-1-C14 in the presence and absence of epinephrine. Addition of epinephrine to intact tissue in an incubation medium high in FFA increases the specific activity of the tissue FFA. When the tissue is incubated in a medium low in FFA, epinephrine induces an increase in the concentration and radioactivity of the tissue FFA. Epinephrine decreases the esterification of palmitate-1-C14 by intact tissue, regardless of the FFA concentration in the medium. This decrease is unrelated to the specific activities of either the medium or the tissue FFA. In homogenates, the decrease in incorporation of palmitate-1-C14 is proportional to the decrease in the specific activity of the FFA induced by epinephrine. Under the influence of epinephrine, FFA released from adipose tissue that was previously charged with palmitate-1-C14 have a specific activity about six times as great as the glyceride fatty acids. This difference is abolished by homogenization of the tissue. These results suggest that the newly synthesized triglycerides exist as a separate pool and are more readily hydrolyzed, thereby contributing FFA to an intracellular FFA pool. The existence of multiple pools of glycerides and FFA in the adipose tissue cell is dependent on the architecture of the cell.
INHIBITION OF14C-ESTRONE METABOLISM IN RAT LIVER MICROSOMES BY 2-HYDROXYESTROGENS AND RELATED COMPOUNDS
Authors: Lazier Catherine , Jellinck P. H.
Published: December 2009

Inhibition studies with compounds having structural features in common with the natural estrogens have shown that 2-hydroxyestrone and 2-hydroxyestradiol are potent inhibitors of the rat liver microsomal system, which converts estrone to water-soluble protein-bound products. Simple phenols and naphthols hydroxylated in the ortho and para positions were also found to be good inhibitors, but the corresponding meta-hydroxylated compounds, as well as various anthraquinones and estrogens substituted in the 6, 10, or 16 positions, were inactive in this respect. The synthetic estrogen, hexestrol, lost its inhibitory activity on conversion to dihydroxy hexestrol, a nonestrogenic analogue. The type of inhibition produced by 2-hydroxyestrone, equilenin, diethylstilbestrol, and menadione has been determined by the Lineweaver–Burk method and shown to be competitive for the first three of these compounds.
CHARACTERISTIC ELECTROPHORETIC PATTERNS OF SERUM PROTEINS OF SEVERAL SPECIES OF SNAKES OF IRAN
Authors: Latifi M. , Shamloo K. D. , Amin A.
Published: December 2009

Paper and starch-gel electrophoresis of serum proteins of several species and subspecies of poisonous and nonpoisonous snakes of Iran have been investigated. The patterns obtained, especially by means of the starch-gel method, are characteristic for each species. Electrophoretic patterns of samples of serum from different individuals of the same species were very similar.
MULTIPLE FORMS OF HUMAN LIVER ESTERASES
Authors: Ecobichon D. J.
Published: December 2009

Zone electrophoresis in starch gel of the water-soluble human liver esterases resulted in the separation of three zones of activity, each composed of several bands. The relative sizes of the enzymes in each zone were studied by utilizing the relative retardation of the electrophoretic migration induced by changes in the concentration of starch. On the basis of graphic analysis, four esterase bands comprising the zone migrating towards the cathode were found to be similar in molecular size or shape. A similar observation was made for seven bands comprising a zone migrating towards the anode. Taken with the substrate specificities and sensitivities toward various inhibitors, these observations strengthen the hypothesis that at least two of the hepatic esterases, an acetylesterase and an aliesterase, exist as multiple forms, differing primarily in net electrical charge.
A SIMPLE PROCEDURE FOR THE STUDY OF INOSITOL PHOSPHATIDES IN CAT BRAIN SLICES
Authors: Palmer F. B. , Rossiter R. J.
Published: December 2009

A procedure is described for the separation of monophosphoinositide (MPI), diphosphoinositide (DPI), and triphosphoinositide (TPI) from small samples of tissue. The method is readily applicable to experiments with tissue slices. It is based upon the finding that MPI is readily extracted into chloroform–methanol (2:1), and DPI and TPI are extracted when 1 part of concentrated hydrochloric acid is added to 300 parts of the solvent. The phosphoinositides are then separated chromatographically on formaldehyde-treated paper.In experiments in which slices of cat brain were incubated in the presence of inorganic32P, the phosphorus compounds of high specific radioactivity remaining in the tissue residue after extraction of lipids and nucleic acids, and referred to previously as "inositide P" or "residue organic P", were found to be chiefly protein-bound DPI and TPI, with small amounts of protein-bound phosphatidyl serine and phosphatidyl ethanolamine.Increasing the concentration of K+ion in the medium from 5.9 mM to 105 mM caused a decrease in the incorporation of inorganic32P into the "lipid extract", MPI, DPI, and TPI of cat brain slices. Addition of chlorpromazine (0.1 mM), or acetylcholine (10 mM) with eserine sulfate (0.5 mM), caused an increase in the incorporation of inorganic32P into the "lipid extract" and MPI, but with no corresponding increase in the incorporation into DPI and TPI.
EFFECTS OF SODIUM PHENYLPYRUVATE ON AMINO ACID FORMATION IN BRAIN
Authors: Itoh T.
Published: December 2009

Rat brain cortex slices were incubated with glucose-U-C14in normal Krebs–Ringer phosphate media and also media 105 mM in potassium ions. Intracellular labelling of amino acids, such as glutamic acid, glutamine, γ-aminobutyric acid, aspartic acid, and alanine, was estimated by radioautography according to the method of Kini and Quastel. The respiration of brain cortex slices was little affected by the presence of phenylpyruvate. However, the formation of these amino acids was strongly suppressed. Moreover, in high-potassium media, the inhibitory effects of phenylpyruvate were greatly magnified. The addition of phenylalanine had no significant effect either on the oxygen consumption or on the amino acid formation when brain cortex slices were incubated with glucose-U-C14.
CHANGES IN MORPHINE- AND CHLORPROMAZINE- N-DEMETHYLASE DURING THE DEVELOPMENT OF TOLERANCE TO CHLORPROMAZINE IN MICE
Authors: Shuster Louis , Hannam Ruth V.
Published: December 2009

The development of tolerance to dihydromorphinone in mice could be prevented by treatment with chlorpromazine. Under certain conditions analgesic tolerance resulted from treatment with chlorpromazine alone. There was a two-to three-fold increase in the activity of dihydromorphinone-N-demethylase and chlorpromazine-N-demethylase in the livers of mice treated with chlorpromazine. The increase in chlorpromazine-N-demethylase was more rapid in mice kept at 33° than in mice kept at 22°, presumably because chlorpromazine-produced hypothermia interfered with protein synthesis in the liver. Mice showed tolerance to the hypothermic effect of chlorpromazine within 1 or 2 days. Tolerance was not related to increased metabolism of chlorpromazine. Treatment with ethionine blocked the chlorpromazine-induced increase in N-demethylase but did not prevent the development of tolerance. Tolerance developed more slowly at 33° than at 22°.
NATURE OF NEWLY SYNTHESIZED RNA IN DEVELOPING RAT BRAIN
Authors: Singh Udai N.
Published: December 2009

Sedimentation characteristics of labelled RNA synthesized in young rat brain slices have been studied by sucrose density gradient centrifugation. A major fraction of the radioactivity derived from adenine-8-C14 in phenol-extractable RNA is shown to be localized in soluble RNA and in relatively small amounts of highly labile fractions in the region lying between 10 S and 20 S. Smaller peaks with S values greater than 30 are also observed. The radioactivity profile of a rapidly labelled RNA isolated from interphase is found to be in sharp contrast with that of phenol-extractable RNA.
THE UPTAKE OF GLYCINE BY RAT BRAIN MITOCHONDRIA
Authors: Nukada T.
Published: December 2009

Rat brain mitochondrial pellets are able to accumulate glycine by a sodium-dependent and ouabain-sensitive process which is not potassium dependent. This process does not occur in liver or kidney mitochondria. Glycine uptake by brain mitochondria is not affected by the addition of ATP, NAD, or other cofactors, but it is inhibited by dinitrophenol and, competitively, by certain amino acids. Data obtained by the use of various concentrations of sodium ions or of sucrose indicate that the uptake of glycine by brain mitochondria is closely linked with their structural integrity.