bluuebunny/crossref_metadata_2025 huggingface dataset:
THE INFLUENCE OF POTASSIUM ION UPON GLUCOSE UPTAKE AND GLYCOGEN SYNTHESIS IN THE ISOLATED RAT DIAPHRAGM
Authors: Clarke D. W.
Published: December 2009

The amounts of glucose taken from a medium, and the amounts of glycogen synthesized, by rat hemidiaphragms were studied under various conditions. High concentrations of potassium ion inhibited the glucose uptake and there was also a reduced net glycogen synthesis. Glycogen breakdown was probably not increased by high potassium ion concentration. The effect of potassium was most marked when conditions were such that one would ordinarily expect a considerable glucose uptake or glycogen synthesis. The action of insulin was not peculiarly susceptible to potassium ion inhibition.
SKIN METABOLISM IN RATS EXPOSED TO COLD
Authors: DesMarais André
Published: December 2009

In a study of skin metabolism, it has been found that the activity of the succinic dehydrogenase in this tissue is increased during exposure to cold and that this increase is prevented by administration of sodium ascorbate.
ANTIOXIDANTS AS INHIBITORS OF LINOLEATE OXIDATION CATALYZED BY PLANT LIPOXIDASE AND BY HEMOLYZATES OF HUMAN ERYTHROCYTES
Authors: Collier H. Bruce , McRae Sheila C.
Published: December 2009

Hemolyzates of human erythrocytes catalyzed the oxidation of linoleate at pH 7 but not at pH 9. Hence the erythrocytes contained no lipoxidase and the catalytic action was probably due to hemoglobin. However, the time-activity curves for hemolyzates and for crystalline hemoglobin were not identical in shape. The oxidation of linoleate at pH 7 by plant lipoxidase was powerfully inhibited by phenothiazine and by phenylhydrazine. These compounds, and also α-tocopherol and α-naphthol, inhibited the catalytic activity of hemolyzates and of crystalline hemoglobin. It is probable that phenothiazine and phenylhydrazine act as antioxidants in these systems. Antioxidants in vivo may possibly play a role in protecting the unsaturated fatty acids of the erythrocyte membrane from oxidation catalyzed by hemoglobin.
A NOTE ON THE EFFECT OF AUREOMYCIN ON THE RESPONSE OF THE RAT TO VITAMIN D
Authors: Murray T. K. , Campbell J. A.
Published: December 2009

The response of rachitic rats to doses of vitamin D, as measured by the line test, was increased by the addition of aureomycin to the rachitogenic diet. The weight gain of these animals was also increased by the antibiotic. In the absence of vitamin D aureomycin had no effect on either calcification or weight gain.
RENAL RESPONSES TO HYPERVOLEMIA IN THE DOG
Authors: Young I. E. , Pearce J. W. , Stevenson J. A. F.
Published: December 2009

Kidney function studies and cardiovascular measurements were made on anesthetized dogs rendered hypervolemic with infusions of dextran, plasma, whole blood, or saline. The infusions, equal in volume to the calculated initial blood volume, were given at a standard rate except those of dextran which were infused at a faster and at a slower rate. A diuresis resulted from all infusions except that of whole blood; a greater diuresis accompanied slow infusions of dextran compared with the effect of more rapid infusions of dextran of similar volume. With all infusions, except that of saline, there was no increase in glomerular nitration rate. It is inferred that part of the diuresis with dextran infusions, as well as that with plasma infusions, was due to alteration in tubular function. The RBF was normal or decreased during all infusions; it is reasoned that renal afferent vasoconstrictor activity increased during hypervolemia produced by infusions other than saline. Some possible factors in the production of the diuresis, other than the volume increase alone, are discussed.
OBSERVATIONS ON THE ACTION OF HEXAMETHONIUM BROMIDE IN TOURNIQUET SHOCK IN RATS
Authors: Spoerel W. E. G. A.
Published: December 2009

Rats subjected to tourniquet shock were treated with hexamethonium bromide (C6), a ganglionic blocking agent. The effect of this agent on survival, blood pressure, fluid loss, and hemoconcentration was studied. Hemoglobin as determined by the cyanhemoglobin method was used as an indicator of hemoconcentration. The fluid loss into the injured hindlegs was measured by the estimation of the fluid content of muscle tissue. The survival rate was significantly improved by administration of C6 at the time the tourniquets were released. Treatment with C6 two and four hours after tourniquet release provided little or no protection. No difference in fluid loss could be detected between treated and untreated rats, but the hemoconcentration was less in treated animals and followed a different pattern. Treated rats showed no blood pressure response to the release of the tourniquets. The protection provided by C6 is thought to be due mainly to its effect on the general circulation.
ON RAT SERUM AMYLASE: III. THE CONTRIBUTION BY VARIOUS TISSUES TO SERUM AMYLASE ACTIVITY
Authors: Wiberg G. Stuart , Tuba Jules
Published: December 2009

The contribution of various tissues to the level of rat serum amylase has been investigated. The pancreas appeared to furnish significant amounts of the enzyme to serum. This was suggested by parallel decreases in pancreatic and serum amylase activity associated with fasting, partial pancreatectomy, and parenteral administration of ethionine. However, increased levels of pancreatic amylase, produced by high dietary concentrations of starch and sucrose, were not paralleled in the serum. Major pancreatectomy indicated that extra-pancreatic sources contribute to serum amylolytic activity. Fasting, partial pancreatectomy, and ethionine injection were followed by decreased amylase levels in serum and intestinal mucosa, and suggested the mucosa as a possible source of the serum enzyme. Depot fat contained appreciable amounts of amylase and is considered as a contributor to serum. This possibility is indicated by the highly significant increase produced in serum and depot fat amylase levels by a high dietary concentration of fat. Moreover a highly significant correlation was found between serum and depot fat amylase levels. It was noted that the high fat diet stimulated amylolytic activity of intestinal mucosa without affecting pancreatic amylase levels. The parotid glands had the highest tissue amylase levels but did not appear to contribute to the serum.
SPECTROPHOTOMETRIC ANALYSIS OF MIXED SOLUTES AND CRUDE ORGAN EXTRACTS
Authors: Annau E.
Published: December 2009

A procedure is presented by which the spectrophotometric separation of two mixed solutes, absorbing in the ultraviolet region, became possible. By the extension of the method to crude organ extracts, absorption spectra characteristic in their main points for proteins could be obtained selectively from the composed spectra of the extracts. At the same time a method is described for the preparation of crude organ extracts showing an apparently maximal transparency.
ULTRAVIOLET LIGHT ABSORPTION IN CRUDE ORGAN EXTRACTS FROM NORMAL MICE AND FROM MICE UNDER THE STRESS OF SOME TOXIC AGENTS
Authors: Annau E.
Published: December 2009

Ultraviolet spectrophotometric studies of brain and liver extracts of normal mice and of mice suffering a progressive aldrin intoxication or an acute cocaine poisoning were described. Using an optical method developed in this Institute and presented in a previous communication, tentative protein spectra characteristic for each individual organ could be obtained. Essential differences could be registered in the absorption spectra from animals poisoned with aldrin or cocaine as compared to the spectra of controls.
THE BINDING OF SULPHATASE BY RAT-LIVER PARTICLES AS COMPARED TO THAT OF ACID PHOSPHATASE
Authors: Viala Renée , Gianetto R.
Published: December 2009

One of the sulphatases of rat liver, like acid phosphatase, is enclosed within cytoplasmic granules. The two enzymes are released from these granules in similar proportions by various treatments.
THE EFFECTS OF ADRENAL CORTICAL EXTRACTS UPON CARBOHYDRATE METABOLISM WHEN MEDIUM COMPOSITION IS ALTERED
Authors: Clarke D. W.
Published: December 2009

The effects of adrenal cortical extract upon glucose uptake and upon glycogen synthesis in the isolated rat diaphragm were studied in three different media. The maximum inhibition by the extract upon the measured effects was seen in a medium which contained both sodium and potassium ions. In media which contained either of these alone as the major cation, there was no significant inhibition.
BIOLOGICAL ASSAY OF THE TOXIN FROM SHELLFISH
Authors: Stephenson N. R. , Edwards H. I. , MacDonald B. F. , Pugsley L. I.
Published: December 2009

A conventional quantal response assay procedure was employed to determine the LD50 of shellfish extracts. The slope of the log dose – response line obtained with butter clam extracts was not significantly different from that found with scallop liver extracts. When kept in a dry, cold state, a lyophilized extract of scallop liver was stable throughout a test period of nearly three years. Such a preparation could be used as a reference standard for the bio-assay of shellfish toxin. Female mice were more susceptible to the paralytic poison than male mice. The LD50 per mouse was related directly to the average body weight of the test animals. The volume of the injection medium had no effect on either the magnitude of the LD50 or the slope of the probit regression line. A highly significant inverse relationship was demonstrated between the toxicity measured in mouse units, a procedure based on the mean death time of the test animals, and the LD50 per kgm. of mouse determined by an assay with an all-or-none response.
EFFECT OF STARVATION ON CHOLESTEROL BIOSYNTHESISIN VITRO
Authors: Migicovsky B. B. , Wood J. D.
Published: December 2009

The components of centrifugal fractionation of liver homogenates from normal and starved rats were examined for cholesterol synthesis and inhibition thereof. Normal liver particulate matter fractions obtained between 700 to 9000 × g and 9000 to 140,000 × g were active with respect to cholesterol synthesis in the presence of clear supernate obtained by centrifugation at 140,000 × g. The particles alone did not synthesize cholesterol. Particles from liver homogenate of starved rats, recombined with clear supernate from starved rats, lacked synthetic activity but clear supernate from liver homogenate of starved rats showed some activity in the presence of normal particles. Degradation of cholesterol occurred with liver particles (700–9000 × g) from both normal and starved rats: the latter preparation also inhibited cholesterol synthesis. Preliminary incubation of clear supernate from normal rats with particles from starved rats, followed by recentrifugation at 140,000 × g, produced a supernate with synthetic activity equal to that obtained with untreated supernate. Preliminary incubation with normal particles gave a supernate with less synthetic activity. This indicated another difference between particulate matter from normal and starved rats.
CARDIAC AUTOMATISM AND CHOLINE ACETYLATION IN RATS ON THIAMINE- AND PANTOTHENIC- ACID-DEFICIENT DIETS
Authors: Beznák A. B. L. , Alphen G. W. H. M. van
Published: December 2009

The choline acetylating activity of extracts of the acetone powders of hearts of rats fed on diets deficient in thiamine, in pantothenate, and in thiamine plus pantothenate was found to be the same as it was in rats on a complete synthetic diet, although severe changes in the electrocardiogram (e.c.g.) were present in rats on the two thiamine-deficient diets. These e.c.g. changes were the same as the ones described in rats on diets deficient in other factors besides thiamine. The rats on the pantothenic-acid-deficient diet grew as normals did and no e.c.g. abnormalities were seen in them. The symptoms of thiamine deficiency were attenuated and their appearance delayed when pantothenate also was deleted from the diet.
THE METABOLIC EFFECTS OF INTRAVENOUSLY ADMINISTERED ALDOSTERONE IN A TOTALLY ADRENALECTOMIZED HUMAN
Authors: Beck J. C. , Giroud C. P. , Dyrenfurth I. , Venning E. H.
Published: December 2009

Six hundred micrograms of aldosterone administered intravenously to a totally adrenalectomized patient caused water retention and weight gain without apparent alteration in the sodium and potassium balance. A marked increase in the urinary nitrogen excretion occurred during the aldosterone infusion.
LEVELS AND PARTITION OF THE FOWL'S SERUM PROTEINS IN RELATION TO AGE AND EGG PRODUCTION
Authors: Vanstone W. E. , Maw W. A. , Common R. H.
Published: December 2009

The level of total serum protein in the fowl has been followed from the 14th day of incubation to the 13th week of egg production. Serum proteins have been fractionated concurrently by zone electrophoresis in filter paper. Serum protein level in the 14-day embryo was 0.9 gm./100 ml. and the protein comprised a prealbumin fraction, albumin, α2- and β-globnlins. Sera from chicks aged seven days no longer contained a prealbumin fraction but α1-,α3- and γ-globulin fractions had appeared by this stage and the protein level had reached 2.3 gm./100 ml. Total serum protein in females increased to a maximum of about 5.4 gm./100 ml. in the week before laying of the first egg. By that time two new protein fractions had appeared. These new fractions accounted for the greater part of the increase over the levels (4.0 gm./100 ml.) prevailing in the prepuberal stage. Serum protein level declined during the first three weeks of laying to average levels below 4.0 gm./100 ml.; and this decline appeared to affect albumin and α1-globulin as well as the new fractions. As laying progressed, the total serum protein tended to regain a level around 4.0 gm./100 ml. The electrophoretic pattern also tended to return towards that prevailing in the week before laying. Some tentative correlations of the results of zone electrophoresis with published results for free electrophoresis of fowl serum proteins are presented.
CYTOCHROME OXIDASE AND SUCCINIC OXIDASE ACTIVITY IN MAMMARY GLAND MITOCHONDRIA OF LACTATING RATS
Authors: Tuba Jules , Orr Patricia F. , Wiberg G. Stuart
Published: December 2009

The effect of lactation on some oxidative enzymes of rat mammary gland mitochondria was examined. Cytochrome oxidase levels were nearly doubled during lactation. Succinic oxidase activity was not demonstrable in breeder female rats four days after the cessation of nursing, or in a control group (non-lactating breeder females, which had weaned their young at least four weeks previously), but during the nursing period considerable activity of the enzyme was observed. Succinic dehydrogenase activity was negligible in mitochondria during involution of rat mammary tissue. On the other hand appreciable anaerobic glycolysis occurred in the resting gland. The greatly increased metabolic activity associated with lactation is reflected in the altered behavior of some of the enzymes of rat mammary gland mitochondria.
WORKING BASIS FOR THE TRACER MEASUREMENT OF TRANSFER RATES OF A METABOLIC FACTOR IN BIOLOGICAL SYSTEMS CONTAINING COMPARTMENTS WHOSE CONTENTS DO NOT INTERMIX RAPIDLY
Authors: Wrenshall Gerald A.
Published: December 2009

A working basis is developed for the simultaneous measurement, by means of an isotopic or other label, of all transfer rates of a given chemical element in systems where its transfer between spatially separate compartments of the system must occur by way of a central compartment (mammillary systems). In addition to the measurement of all rates of transfer, the amount of the element within each compartment of a mammillary system can be determined from the same experimental data. The method is applicable in open as well as closed mammillary systems which may or may not be in a state of dynamic equilibrium, and in which rapid uniform intermixing of the element does not occur in peripheral compartments. A basis for the determination of the total rates of appearance and disappearance of multiatomic as well as monatomic substances in any compartment of a system of compartments is presented, without exchanges being restricted to mammillary or other constrained systems. However, only in compartments where chemical transformation of such molecular substances does not occur can the calculated rates of appearance and disappearance of the metabolite be interpreted as rates of transfer into and out of the compartment. Specific problems relating to the tracer measurement of transfer rates in the mammillary systems of living organisms are considered, and a check list is presented for evaluating published experimental results involving tracers as potential sources of information on transfer rates in biological systems determined by means of the above bases for calculation.
EFFECTS OF INSULIN ON RATES OF GLUCOSE TRANSFER IN THE DEPANCREATIZED DOG
Authors: Henderson Margaret J. , Wrenshall Gerald A. , Odense Paul
Published: December 2009

An attempt to answer the question as to whether insulin acts to lower blood glucose by increasing utilization, or by decreasing production, or by both, has been made using a new experimental approach. A trace dose of radioactive glucose was injected into each of six postabsorptive depancreatized dogs which had been deprived of exogenous insulin for 66 hr. Blood samples were collected before and after the intravenous injection of insulin, and plasma glucose concentration and specific activity were measured. From these data the simultaneous rates of appearance and disappearance of plasma glucose were calculated for a sequence of time intervals, both before and after insulin, by a method which did not assume dynamic equilibrium. Previous in vivo experiments using radioactive tracers to measure rates of production and utilization of glucose have been made in animals which were in steady states, either with or without insulin, and the effects of insulin were ascertained by comparison of the state with insulin and the state without insulin. The method described in this paper has made it possible to follow the effects of insulin while it is acting in one and the same animal. Insulin was found to cause an abrupt and marked increase in the rate of disappearance of glucose, and this increased rate became less with time, reaching the preinsulin level in about 90 min. Insulin caused a slower and much smaller decrease in the rate of appearance, but the decrease became greater with time during the three hour period of observation. Thus, it appeared that insulin acted in vivo both to increase the utilization of glucose and to decrease its production, but the effects differed in magnitude and in speed of response.
DIRECT VERSUS TRACER MEASUREMENT OF TRANSFER RATES IN A HYDRODYNAMIC SYSTEM CONTAINING A COMPARTMENT WHOSE CONTENTS DO NOT INTERMIX RAPIDLY
Authors: Schachter Harry
Published: December 2009

The working basis for the measurement of transfer rates between compartments developed in a preceding paper by Wrenshall is demonstrated for a closed hydrodynamic mammillary system in dynamic equilibrium. Rapid uniform intermixing of the water in one of the peripheral compartments was prevented by the presence there of glass tubelets. Rates of water transfer were measured directly with a graduate cylinder and stop watch, and calculated by means of equation [9] of the preceding paper, using crystal violet dye as tracer. It is clearly demonstrated that to measure transfer rates between the central compartment and the non-uniformly mixing peripheral compartment, it is necessary to extrapolate all tracer measurements to lime of tracer addition to the central compartment. The amount of water contained in the central compartment was measured in the same experiment both directly and by tracer dilution. The procedures and problems involved in performing the above model experiment are compared with those encountered in the tracer measurement of transfer rates and compartmental contents in living mammillary systems.
STEREOSPECIFICITY IN THE ENZYMATIC HYDROLYSIS OF TABUN AND ACETYL-β-METHYLCHOLINE CHLORIDE
Authors: Hoskin F. C. G. , Trick G. S.
Published: December 2009

The hydrolysis of the powerful cholinesterase inhibitor, tabun, at pH 7 to 7.5 by a rat serum enzyme in bicarbonate buffer involves two simultaneous first-order reactions. A fast, enzyme-catalyzed reaction destroys the toxic dextrorotatory isomer of tabun. The much slower hydrolysis of the levorotatory and apparently non-toxic isomer is probably a non-enzymatic reaction. The enzymatic hydrolysis of acetyl-dl-β-methylcholine chloride by a rat brain homogenate has been studied as a model reaction. Only one-half of the racemic compound is hydrolyzed in contrast to the complete hydrolysis of acetylcholine chloride by the same enzyme source. These results and the results of toxicity studies on the hydrolyzing solution indicate that true cholinesterase hydrolyzes only the dextrorotatory isomer of acetyl-dl-β-methylcholine chloride.
THE EFFECT OF DIFFERENT DEGREES OF SUBDIAPHRAGMATIC AORTIC CONSTRICTION ON HEART WEIGHT AND BLOOD PRESSURE OF NORMAL AND HYPOPHYSECTOMIZED RATS
Authors: Beznák Margaret
Published: December 2009

The aortae of groups of normal and hypophysectomized rats were constricted with rings of five different sizes (0.93, 0.83, 0. 74, 0.71, and 0.63 mm. diameter). In normal rats constriction caused an increase in heart weight and blood pressure which was the greater the narrower the constriction. If constriction exceeded 0.74 mm., cardiac hypertrophy reached extremely high values, while the blood pressure was lower than in groups with less constriction. The blood pressure response to Adrenalin or Infundin increased in proportion to the degree of constriction down to 0.74 mm.; greater constriction reduced the response. In hypophysectomized rats no degree of aortic constriction produced hypertension or cardiac hypertrophy, yet the increase in blood pressure after Adrenalin or Infundin was as great as in the normal intact rats.
CHANGES IN HEART WEIGHT AND BLOOD PRESSURE FOLLOWING AORTIC CONSTRICTION IN RATS
Authors: Beznák Margaret
Published: December 2009

Blood pressure measurements in the carotid and femoral arteries of rats after subdiaphragmatic aortic constriction, taken at times varying from immediately afterwards to five days after, indicate that increased carotid pressure precedes cardiac enlargement in these animals. The large drop in femoral blood pressure within the first few hours after aortic constriction seems to be due—at least partly—to stimulation of the pressoreceptors by the increased aortic–carotid pressure. Hypertrophy of the left ventricle can be demonstrated on the second day after constriction. The maximum height of carotid pressure obtainable after epinephrine injection rises with the time after constriction, while the rise over the preinjection value does not increase.
THE STIMULATION AND INHIBITION OF ENZYME CATALYZED REACTIONS
Authors: Scholefield P. G.
Published: December 2009

An analysis has been made of the effect of complexing agents on the velocity of enzyme catalyzed reactions. Complexing agents are here defined as agents which combine with enzyme proteins in a manner which results in a change in the catalytic activity of the enzyme, i.e. they produce inhibitions or stimulations. From the analysis it is possible to deduce equations governing competitive, non-competitive, "apparent" competitive, and "apparent" non-competitive inhibitions. The cases of competitive and non-competitive stimulations where the complexing agent is non-essential are considered and the corresponding equations deduced. The effects of coenzymes having various affinities for the enzyme and for the enzyme combined with substrate are also analyzed. In the case of the "apparent" non-competitive stimulation of fumarase by phosphate, it is shown that the results obtained by previous workers are entirely in agreement with the present kinetic analysis.
SPECTROPHOTOMETRIC ANALYSIS OF NUCLEIC ACIDS IN PROTEIN SOLUTIONS AND IN CRUDE ORGAN EXTRACTS
Authors: Annau E.
Published: December 2009

A spectrophotometric procedure has been presented by which an absorption spectrum, essentially characteristic for nucleic acids, could be obtained from mixed nucleic acid protein solutions, and mouse liver extracts. To examine the efficiency of the method for nucleoprotein complexes, spectra from purified calf thymus nucleohiston were prepared showing the absorption curves of both of its components: nucleic acids and histon.
RELATIONS THYROÏDE–SURRÉNALES DANS L'ADAPTATION AU FROID
Authors: DesMarais André
Published: December 2009

Recent studies have stressed the relations between the thyroid and adrenal glands. A review of the literature on this subject leads to the hypothesis that a quantitative relationship between the thyroid and corticoadrenal hormones seems to play an important part in the defence of the organism exposed to cold. Experimental work on normal, adrenalectomized, thyroidectomized, and adrenalectomized–thyroidectomized rats receiving various doses of cortisone and (or) thyroxine emphasizes the existence of such a quantitative relation between thyroxine and cortisone. The administration of thyroxine can prevent the catabolic action of cortisone in animals exposed to cold. Analysis of the results seems to show that exposure to cold is not a stress, provided the increase in thyroid function is sufficient to meet the requirements of the organism. From these experiments and other results obtained in this laboratory, a new basis can be laid down for the understanding of the beneficial effects of ascorbic acid in animals exposed to cold. It has been shown repeatedly that administration of ascorbic acid can prevent to some extent the catabolic effects of exposure to cold. It has also been observed that ascorbic acid administration decreases the degree of thyroid hyperactivity in animals exposed to cold. On the other hand, it has been shown that thyroxine administration can also prevent the catabolic effects of exposure to cold. It seems logical to assume that ascorbic acid might, in some way, reduce the thyroid hormone requirements of the cold exposed animals. Up to the present, only indirect evidence of such a mechanism has been obtained; it is hoped that further experimentation will provide a definite insight into this problem.
THE RESPIRATION OF ASCARIS LUMBRICOIDES EGGS
Authors: Passey Richard F. , Fairbairn Donald
Published: December 2009

The rate of oxygen consumption of developing ascaris eggs decreased rapidly to a minimum after 1.5 days, and thereafter increased to a maximum at 10 days, when the embryos were vermiform. During the 10–20 day period, when the embryo matures and molts once in the egg, the respiration decreased steadily, and continued to decrease more slowly until at 140 days the rate was scarcely measurable. Nevertheless, the eggs remained viable and hatched readily in the mouse gut. Cytochrome c and cytochrome oxidase could not be detected by direct assay or isolation. However, the high sensitivity of the respiration to carbon monoxide (in the dark), to cyanide, and to azide, and the low sensitivity to carbon monoxide (in the light) and to decreasing partial pressures of oxygen, indicated that oxidases such as the flavoproteins, phenolases, and peroxidases were unlikely respiratory catalysts, and that cytochrome oxidase, or a similar and hitherto undescribed enzyme, was the major component of the terminal respiratory enzyme system.
METABOLISM OF RADIOACTIVE β-(3,4-DIHYDROXYPHENYL)-ALANINE-α-C14IN THE ALBINO RAT
Authors: Pellerin Joseph , D'Iorio Antoine
Published: December 2009

When DL-3,4-dihydroxyphenylalanine-α-C14(DL-dopa-α-C14) was injected into rats, 80% of the radioactivity was recovered from urine and 2% from respiratory carbon dioxide. The urine was examined by descending paper chromatography and the following radioactive substances have been identified: dopa, hydroxytyramine, 3,4-dihydroxyphenylpyruvic acid, and 3,4-dihydroxyphenylacetic acid. The urinary hydroxytyramine is partially conjugated, presumably as a glucuronide or as a sulphate. Evidence is also presented which indicates that 5,6-dihydroxyindole is one of the metabolites present in urine. Radioactive epinephrine or norepinephrine could not be detected in either urine or suprarenal gland.
A NOTE ON THE ENERGY OF ACTIVATION OF THE AMYLASE IN VARIOUS HUMAN BODY FLUIDS
Authors: Kovacs Leslie , Tuba Jules
Published: December 2009

The activation energy was determined for the amylase present in the following fluids obtained from the human body: urine, duodenal fluid, saliva, and normal serum, as well as serum from patients with mumps, acute pancreatitis, and carcinoma of the head of the pancreas. Over a temperature range of 4°–37.4 °C., with starch as a substrate, the value of the energy of activation was similar in all cases to that for bacterial α-amylase, and the mean value was 13,740 ± 200 cal./mole. Partial heat inactivation of the enzyme was evident in some cases at 37.4°. On the basis of the evidence obtained it appears that α-amylase is present in all the body fluids examined.
THE ALTERATION OF INTRACELLULAR ENZYMES: IV. KINETICS OF CATALASE ALTERATION INDUCED BY CHEMICAL AGENTS
Authors: Kaplan J. Gordin , Paik Woon-Ki
Published: December 2009

The rate with which n-butanol alters the properties of yeast catalase has been studied as a function of temperature and concentration of altering agent. Activation energies for catalase alteration lay within the rather narrow range of 20–23 kcal./mole, thus confirming a prediction made previously on the basis of the difference in energies of activation for heat destruction of altered and unaltered catalases. Alteration by optimal concentration of butanol was a reaction of zero order. Chloroform also altered yeast catalase with an activation energy within this range of μ values. The close agreement in μ values leads us to conclude that the action of these two altering agents, at all concentrations, is characterized by the same rate-limiting step, even though their action differs in other respects. It was concluded that catalase alteration is probably all-or-none on the molecular level, rather than on the cellular level. Alteration was invariably accompanied by a decrease in the size of the treated cells; alteration was sometimes accompanied by changes in the cytochrome spectrum, but there was no causal connection between these two events. These data are consistent with the interfacial hypothesis, which, in its present crude form, pictures alteration as consisting essentially in the desorption of catalase from some intracellular interface at which it is normally bound in the intact cell.
THE MUSCLE AND INTEGUMENT LIPIDS IN FEMALE ASCARIS LUMBRICOIDES
Authors: Fairbairn Donald
Published: December 2009

Total lipids of the body wall (muscle plus integument) consisted of phospholipids (38%), unsaponifiables (8.1%), and triglyceride acids (47%). The phospholipid fraction contained major amounts of phosphoacetals, lecithins, and phosphatidylethanolamine. Sphingolipids and phosphatidylserine were probably present in smaller amounts. Much of the unsaponifiable matter was similar to, but not identical with, the ascaryl alcohol of the reproductive tissues, although sterols were also present. The triglycerides contained an approximately equimolar mixture of volatile and non-volatile acids. Phospholipid acids, on the other hand, were entirely non-volatile. The integument lipid fractions were similar in amount and kind to those of the muscle.
STUDIES ON THE PRESERVATION OF BLOOD: IV. THE INFLUENCE OF ADENOSINE ON THE GLYCOLYTIC ACTIVITY OF THE ERYTHROCYTE DURING STORAGE AT 4° C.
Authors: Rubinstein David , Kashket Shelby , Denstedt Orville F.
Published: December 2009

Human blood was stored in citrate–dextrose and acidified citrate–dextrose media with and without the addition of adenosine. In both preservative media the adenosine induced an increase in the esterification of phosphate mainly in the form of 2, 3-diphosphoglycerate, and also an increased production of lactate. The increase in lactate formation could not be accounted for entirely by the amount of glucose utilized and it was apparent that the extra amount of lactate must have been derived from the utilization of the ribose component of adenosine. The pH of the blood samples containing adenosine was found to be higher than that of the corresponding control samples. It has been demonstrated that adenosine added to blood is first converted to inosine by deamination and the latter, in turn, is converted to hypoxanthine. The probable route by which the ribose moiety of adenosine is metabolized in the erythrocyte is discussed.
THE ENZYMATIC HYDROLYSIS PRODUCTS OF SARIN
Authors: Hoskin F. C. G.
Published: December 2009

The hydrolysis of the powerful cholinesterase inhibitor, sarin, by a rat serum enzyme leads almost exclusively to isopropyl methylphosphonic acid, neither methylphosphonic acid nor hydrogen methylphosphonofluoridate being formed. When isopropyl methylphosphonic acid is administered to the intact rat, it is excreted unchanged in the urine. It is inferred, therefore, that the metabolism of sarin by the intact rat would lead almost exclusively to isopropyl methylphosphonic acid.
SEASONAL RECRUDESCENCE OF THE THYMUS IN ADULT BIRDS
Authors: Höhn E. O.
Published: December 2009

The thymus of adult mallards and house sparrows of both sexes and of female robins shows a marked enlargement following the annual breeding season. In male robins the thymus begins to enlarge earlier, almost synchronously with the testes. Histologically the enlarged thymus becomes indistinguishable from the uninvoluted thymus of immature birds, showing lobulation and development of a cortex and medulla. In the atrophic thymus found in adults for most of the year these two zones are not recognizable. The bursa Fabricii of adults does not enlarge at any time. Evidence of a similar thymus enlargement in some other species of birds is presented. The distribution of thymus tissue in passerine birds and hawks differs from the well known arrangement in the chicken; the passerine pattern is illustrated. It was not possible to bring about thymic enlargement out of season by castration or unilateral adrenalectomy in mallards.
THE STERIC FACTOR IN THE HYDROLYSIS OF β-1,4′-OLIGOGLUCOSIDES BY MYROTHECIUM CELLULASE
Authors: Whitaker D. R.
Published: December 2009

A comparison of the rate constants and activation energies for the hydrolysis of cellobiose, cellotriose, cellotetraose, and cellopentaose by Myrothecium cellulase showed that while the rate constant was increased by a factor of about 450 as the degree of polymerization (D.P.) of the substrate was increased from two to five, the activation energy remained at about 12,000 cal. The results are interpreted, in terms of classical collision theory, as indicating that the increase in rate constant with D.P. is determined by an increase in the steric factor with D.P. Addition of a β-linked sorbityl group to an oligoglucoside increased the rate constant; the increase was less than that from addition of an anhydroglucose unit and, relative to the latter, diminished as the D.P. of the chain undergoing addition was increased. Exposing the enzyme to conditions favoring thermal or surface denaturation caused varying losses in enzymic activity towards the four oligoglucosides; wherever the loss in activity towards one oligoglucoside differed substantially from the loss in activity towards any other oligoglucoside, the greater loss was shown towards the substrate of lower D.P. The results are discussed.
THE METABOLISM OF THE ERYTHROCYTE: X. THE INORGANIC PYROPHOSPHATASE OF THE ERYTHROCYTE
Authors: Malkin A. , Denstedt O. F.
Published: December 2009

The activity of the pyrophosphatase which catalyzes the hydrolysis of inorganic pyrophosphate in the erythrocyte of the human, the rabbit, and the chicken is confined entirely to the cytoplasm of the cell. Following preincubation, the enzyme activity in the human erythrocyte is diminished, but pre-incubation in the presence of cysteine or glutathione prevents the diminution of the enzyme activity. Aging of the hemolyzate of the human erythrocytes results in a marked loss of the inorganic pyrophosphatase activity. The diminished activity can be restored by the addition of cysteine or glutathione to the reaction mixture; but after the hemolyzate has aged for five or six days at 5 °C, the loss in the enzyme activity can no longer be restored with these reagents. Fluoride and calcium ions inhibit the activity of the enzyme, while magnesium ions are essential for its activity. Calcium is a noncompetitive inhibitor, while the inhibition by fluoride is of a "quadratic" nature. If a constant ratio of magnesium to pyrophosphate is maintained, the quadratic inhibition can be converted to the "uncompetitive" type of inhibition.
THE METABOLISM OF THE ERYTHROCYTE: XI SYNTHESIS OF DIPHOSPHOPYRIDINE NUCLEOTIDE IN THE ERYTHROCYTE
Authors: Malkin A. , Denstedt O. F.
Published: December 2009

DPN pyrophosphorylase activity has been demonstrated in chicken erythrocytes, but could not be found in rabbit reticulocytes nor in human or rabbit erythrocytes. In the erythrocyte of the chicken, the activity was confined to the particulate fraction, which consists mainly of cell nuclei. The implications of these findings with respect to the maturation of the erythrocyte and the metabolic interrelationship between the nucleus and the cytoplasm are discussed.
THE ROLE OF A-ESTERASE IN THE ACUTE TOXICITY OF PARAOXON, TEPP, AND PARATHION
Authors: Main A. R.
Published: December 2009

The liver and serum A-esterase activity was determined in normal rats and in rats which four days previously had been fed a massive sublethal dose of aldrin. Aldrin pretreatment doubled the A-esterase activity in the liver and halved it in the serum. The intravenous toxicity of paraoxon increased slightly following aldrin pretreatment, while the oral toxicity decreased threefold. These results indicated that the A-esterase activity of the liver mediates the oral toxicity, and that the serum activity influences the intravenous toxicity. The latter conclusion was verified by the preparation of a partially purified concentrate of rabbit serum A-esterase. The concentrate was intravenously injected into rats. The serum A-esterase activity increased three- to five-fold, and the acute toxicity of paraoxon decreased significantly. Following aldrin pretreatment the oral toxicity of TEPP decreased slightly, while the intravenous toxicity remained unaltered. This result is explained by the relative activity of A-esterase toward paraoxon and TEPP. Parathioa intravenous toxicity increased two- to three-fold following aldrin pretreatment. Comparison of paraoxon with parathion experiments suggested that aldrin pretreatment results in the inhibition of the 'in vivo' conversion of parathion to paraoxon. The serum esterase hydrolyzing phenylbenzoate in rat and rabbit was found to be the B-type esterase of Aldridge.
THE METABOLISM OF THE ERYTHROCYTE: XIII. ENZYME ACTIVITY IN THE RETICULOCYTE
Authors: Rubinstein D. , Ottolenghi P. , Denstedt O. F.
Published: December 2009

The object of the study was to ascertain the changes that occur in the activity of the enzymes of the reticulocyte during its maturation to the normocyte (adult erythrocyte). Blood specimens were taken from rabbits in which a severe anemia and a pronounced reticulosis (50–90% reticulocyte count) had been produced by giving the animals subcutaneous injections of acetylphenylhydrazine. Succinic dehydrogenase, cytochrome oxidase, and DPN-ase were found to be confined to the insoluble fraction of the cells while glucose-6-phosphate dehydrogenase and pyrophosphatase were found only in the soluble fraction (stroma-free hemolyzate). Isocitric, lactic, and malic dehydrogenases, fumarase, aconitase, and hexokinase were found to be present in both fractions. The activity of fumarase, hexokinase, and pyrophosphatase is much lower in the normocyte than in the reticulocyte while that of the isocitric, lactic, and malic dehydrogenases and of DPN-ase was of the same order in both types of cell. Aliquots of blood specimens were kept at 37 °C. for 12 hr. and the activity of numerous enzymes was followed at two-hourly intervals. The enzymes which are more active in the reticulocyte undergo a diminution in activity concurrently with the decrease in the reticulocyte count. Succinic dehydrogenase, cytochrome oxidase, and aconitase are absent from the normocyte. The significance of these changes with respect to the maturation of the reticulocyte is discussed.Exposure of hemolyzates of the blood specimens to the enzyme ribonuclease, to destroy any ribonucleic acid that may be present, did not alter the activity of any of the enzymes tested. The DPN-ase of the reticulocyte, as in the normocyte, was found to be a nucleosidase which splits the linkage between nicotinamide and ribose.
SPECTROPHOTOMETRIC ANALYSIS OF PROTEINS BY A SELECTIVE FILTER TECHNIQUE
Authors: Annau E.
Published: December 2009

Ultraviolet absorption spectra of characteristic shapes and vibrational fine structures have been produced of serum albumin, ovalbumin, casein, and gelatin. This was achieved by a method in which a standard reference solution of an appropriate xanthine concentration was used as an optical filter for the spectrophotometric measurements.
THE GASTRIC ENDOCRINE AND EXOCRINE RESPONSE TO HISTAMINE IN DOGS AND EFFECT OF PASSAGE OF BLOOD THROUGH THE GASTRIC AND HEPATIC VESSELS ON ITS PEPSINOGEN CONTENT
Authors: Kowalewski K. , Norvell Jr. S. T. , MacKenzie Walter C.
Published: December 2009

Subcutaneous histamine in dogs in a dose of 5 mgm. per kgm. of body weight provoked a significant increase in gastric pepsin secretion over a four-hour period. The increased pepsin production was accompanied by increased secretion of free HCl, increased volume of gastric juice, and elevation of plasma pepsinogen in the same experimental period. Plasma pepsinogen levels, before and after histamine, were investigated in a gastric artery, a gastric vein, the portal vein, a hepatic vein, and a cephalic vein. The enzyme concentration was significantly higher in the gastric vein than in the gastric artery and this difference was accentuated following histamine administration. These findings were attributed to endocrine secretion of pepsinogen by the zymogenic cells of the gastric mucosa. There was no evidence that pepsinogen concentration is altered as the blood traverses the liver.
THE RELATIVE POTENCY OF ADRENAL CORTICOIDS BY THE THYMUS INVOLUTION METHOD
Authors: Stephenson N. R.
Published: December 2009

An adrenal corticoid which has an α-ketolic grouping at C17, a ketone or β-hydroxyl at C11, a ketone at C3, and a double bond in the 4,5 position is able to involute the thymus gland of the weanling rat. The thymolytic activity of an 11-oxycorticosteroid is increased approximately 3 to 3.5 times by the addition of an α-hydroxyl at C17. The ability of a 17-hydroxycorticosteroid to cause thymic atrophy is enhanced 1.2 times by acetylation at C21, 1.5 times by replacement of a ketone at C11 with β-hydroxyl group, 4 to 5 times by the formation of a 1,2 double bond, and 8 to 10 times by the introduction of a fluorine atom in the α position at C9. The potency of Δ1-11-oxycorticosteroids relative to naturally occurring corticoids is significantly greater when the steroids are injected in an aqueous medium than when they are given in corn oil. The relative activities of adrenal corticoids as determined by the thymus involution method do not differ significantly from those obtained by other glucocorticoid bio-assays.
THE DEGRADATION OF DESOXYRIBONUCLEIC ACID DURING ALKALINE HYDROLYSIS
Authors: Hurst R. O.
Published: December 2009

The extent of alkaline degradation of desoxyribonucleic acid (DNA) was determined by following the formation of organic phosphate soluble in 10% trichloroacetic acid solution and the liberation of ammonia. Hydrolysis of DNA with 1 N sodium hydroxide at 100 °C. for four hours was required to effect complete formation of acid-soluble oligonucleotides and the ammonia liberated was equivalent to the estimated amino nitrogen content of the DNA.
ELECTROPHORESIS OF AUTOPROTHROMBIN AND BIOTHROMBIN
Authors: Seegers Walter H. , Abe Takeshi , Fenichel Richard L.
Published: December 2009

Concentrates of biothrombin and autoprothrombin were prepared from purified prothrombin and subjected to electrophoresis. The mobility of biothrombin is less than that of prothrombin. The mobility of autoprothrombin is less than that of biothrombin. The biothrombin and autoprothrombin preparations examined were not electrophoretically homogeneous. Prothrombin dissociates during electrophoresis at high voltage gradients. Since this does not occur with biothrombin and autoprothrombin, it seems likely that electrophoretically homogeneous derivatives of prothrombin can be obtained with further purification work.
COMPARATIVE BIOCHEMICAL STUDIES ON NORMAL AND ON POLIOMYELITIS INFECTED TISSUE CULTURES: I. OBSERVATIONS ON SYNTHETIC NUTRIENT MIXTURES INCUBATEDWITH TISSUE CULTURES OF NORMAL KIDNEY
Authors: Kovacs Ernest
Published: December 2009

Illustrative examples are given of change in turbidity values of complete and incomplete media used for in vitro cultivation of rhesus monkey kidney tissue. Pools of routine material were examined. The main interest was focused on enzymes directly or indirectly connected with nucleic acid metabolism. The presence and behavior of acid and alkaline monoesterases, 5-nucleotidase, simple nucleotidases, two different types of ribonuclease, and two desoxyribonucleases are described and activity of other enzymes occasionally demonstrated. As a working hypothesis, the bearing of these findings on cell physiology and on pathology of poliomyelitis virus infection is discussed.
THE CHEMISTRY OF THE PHOSPHOINOSITIDES
Authors: Folch J. , LeBaron F. N.
Published: December 2009

The name of inositol phosphatides or phosphoinositides is given to a rather heterogeneous group of substances having in common the presence of inositol, phosphoric acid, and fatty acid(s) among their constituents. The first evidence of their natural occurrence was obtained by Anderson, in 1930, who showed their presence in the lipides of the tubercle bacillus. Since then they have been found in many animal and vegetable tissues, and some of them have been isolated as relatively pure compounds. The majority, if not all of them, are acidic substances which, when prepared by the use of neutral solvents, are obtained as monophosphates of inorganic bases. The constituent inositol is present as a monoester of phosphoric acid, except in the case of brain diphosphoinositide, where it occurs as inositol metadiphosphate. With one possible exception, phosphoinositides contain 1 mole of glycerol per mole of inositol; less commonly, they contain carbohydrates and amines. While valuable information has been obtained on certain details of their chemical structure, in no case has the identification of a phosphoinositide been completed.
CHEMISTRY OF THE SPHINGOLIPIDES
Authors: Carter H. E. , Galanos Demetrius S. , Fujino Y.
Published: December 2009

Chemical studies leading to the elucidation of the structures of sphingosine, cerebrosides, sphingomyelin, and cerebroside sulphuric acid are reviewed. The general nature of the complex sphingolipides (ganglioside, hematoside, globoside, strandin, polycerebroside) is discussed. Preliminary studies on the nature of the phytosphingosine-containing lipides of corn phosphatides are presented.