bluuebunny/crossref_metadata_2025 huggingface dataset:
THE ANTIACCELERATOR EFFECT OF VERATRAMINE ON THE ISOLATED PERFUSED HEART OF THE CAT
Authors: Murnaghan Maurice F.
Published: December 2009

When isopropylarterenol was continuously infused in the isolated perfused heart of the cat, the heart rate remained at a steady elevated level for more than 2 hours. Veratramine selectively antagonized the accelerator effect of isopropylarterenol, and the dose required to cause a 50% reduction in acceleration (I50) was determined. The mean I50value in 13 experiments (mean of the 13 individual I50values) is 0.415 micromolar (μM) with fiducial limits of 0.182–0.648. Cardiac irregularities, arising from the sinoauricular node, occurred in seven out of 13 experiments after the administration of veratramine. The results indicate that in this preparation coronary flow is related to amplitude but is independent of heart rate.
THE EFFECT OF INGESTED CHLORTETRACYCLINE ON SOME HYDROLASES AND ORGANS ASSOCIATED WITH THE DIGESTIVE PROCESS IN GROWING PIGS: II. PANCREAS–DRY WEIGHT, FAT CONTENT, PROTEASE, AND AMYLASE ACTIVITY
Authors: Vonk M. A. A. , McElroy L. W. , Bowland J. P. , Berg R. T.
Published: December 2009

Results of experiments to investigate the effect of dietary chlortetracycline on pancreas dry weight and on the crude fat content and hydrolase activity of the gland are presented. Chlortetracycline fed at a level of 20 g. per ton of feed caused an increase in rate of gain and efficiency of feed utilization by pigs between the ages of 9 and 17 weeks. An effect on the pancreas was indicated by significant increases in: (a) dry weight, (b) total protease and amylase activity, and (c) amylase activity per gram dry matter of the glands from animals receiving the supplemented ration. The difference remained significant after adjustment for body weight by covariance in the case of amylase activity but not for dry weight or protease activity, indicating that the effect of chlortetracycline on amylase activity was more pronounced than that on rate of gain of pigs, pancreas dry weight, or pancreatic protease activity. No significant difference in the crude fat content of the pancreas attributable to the inclusion of chlortetracycline in the ration was observed.
THE EFFECT OF BZ-55 (CARBUTAMIDE) ON THE GLUCOSE-6-PHOSPHATASE ACTIVITY IN THE LIVERS OF INTACT AND ALLOXANIZED FEMALE RATS
Authors: Hawkins R. D. , Haist R. E.
Published: December 2009

The ingestion of the sulphonylurea BZ-55 (0.5 g./kg. body weight) by normal female rats for 8 days leads to a significant depression in the level of glucose-6-phosphatase activity in the liver of these animals. The glucose-6-phosphatase activity of the liver in alloxanized rats is higher than that of paired-fed control animals. The ingestion of BZ-55 by alloxanized rats causes this activity to be further increased as shown by comparison with the glucose-6-phosphatase activity in alloxanized, individually paired-fed controls. The differences in the effects of BZ-55 in normal and alloxanized animals are discussed.
SENSITIZATION BY INSULIN TO THE DEXTRAN "ANAPHYLACTOID" REACTION
Authors: Adamkiewicz V. W. , Langlois Y.
Published: December 2009

A single subcutaneous injection of crystalline insulin (20 units) sensitizes considerably the rats to the dextran "anaphylactoid" reaction. This is a type of acute serous inflammation. Insulin precipitates the reaction after a very small dose of dextran (0.05–0.01 ml., 6% solution) has been injected into a "shock organ". Without insulin, such small doses of dextran are quite ineffective. Insulin also precipitates the reaction when dextran (1.0 ml., 6% solution) is injected peripherally on the back. In this site and at this dose, it rarely produces the reaction in normal rats. The sensitization manifests itself despite a cortisone pretreatment.
THE NATURE OF THE SUBSTANCES IN DIETARY FAT AFFECTING THE LEVEL OF PLASMA CHOLESTEROL IN HUMANS
Authors: Beveridge J. M. R. , Connell W. F. , Mayer G. A.
Published: December 2009

Three dietary experiments have been performed in which 52, 48, and 38 male students and a few members of staff participated as experimental subjects. In the first experiment 52 subjects ingested for 8 days a diet in which butter provided 60% of calories. During the next 8 days subgroups were given rations supplemented with α-tocopherol or β-sitosterol, substances known to be present in corn oil in significant amounts. The α-tocopherol had no effect but the β-sitosterol caused a highly significant decrease in plasma cholesterol.The same conditions were used for the first 8 days of the second experiment in which 48 subjects participated. The subgroups were given diets in which 30% of calories were supplied by butter and 30% by various corn oil fractions obtained by vacuum distillation. All groups showed highly significant decreases in plasma cholesterol and there did not appear to be any effective fractionation of the plasma cholesterol depressant factor in the corn oil, although the largest drop was obtained in the case of the most volatile fraction derived from the corn oil. This preparation contained most of the unsaponihable material and had a slightly lower iodine number than the other fractions.In the third experiment, 38 subjects ingested for 8 days a diet providing 60% of calories from corn oil. Subgroups were transferred to diets supplying 40% of calories from butter fractions obtained by vacuum distillation. All groups showed highly significant increases, the greatest increase being noted in the case of the most volatile fraction, which contained most of the unsaponifiable material. It has been postulated that the potent plasma cholesterol elevating action of butterfat is at least partly dependent upon the presence of the unsaponifiable fraction. The identity of this factor and whether it acts alone or in conjunction with certain types of fatty acid residues are questions that remain to be answered.
OBSERVATIONS ON THE PHYSIOLOGICAL HALF-LIFE OF SERUM PROTEINS IN THE COCKEREL AND THE LAYING PULLET
Authors: Vanstone W. E. , Oliver W. F. , Maw W. A. , Common R. H.
Published: December 2009

The serum proteins of two cockerels and two pullets were labelled by oral administration of S35-L-methionine. The subsequent decline of specific activity of serum proteins indicated physiological half-lives of approximately 6.5 days for both serum albumin and serum globulin in the cockerels. One pullet continued in active lay and the half-life of its serum albumin was approximately 8.5 days; the decline of specific activity of the globulin fraction displayed a relatively steep initial phase; the succeeding decline gave a half-life of approximately 4.6 days; the half-life of the serum phosphoprotein fraction was probably considerably less. These results are discussed in terms of estimated replacement rates of the proteins. The second pullet stopped laying and the results with this bird are discussed separately. The average specific activity of yolk protein attained a maximum in the egg laid on the 6th day after labelling. The subsequent decline in average specific activity of yolk protein with time followed a logarithmic course.
THE ESTIMATION OF SUBSTITUTED THIOOXAZOLIDONES IN RAPESEED MEALS
Authors: Wetter L. R.
Published: December 2009

A quantitative method is described for the separate determination of thiooxazolidone and isothiocyanate in a single sample of rapeseed. The procedure involves first the estimation of the isothiocyanate, which is removed from the macerated meal by steam distillation. Then the filtered residue is shaken with diethyl ether and the quantity of thiooxazolidone in the extract is determined spectrophotometrically at 248 mμ. Recoveries of thiooxazolidone added to rapeseed meal are quantitative and precautions required to give reproducible results are outlined. The thiooxazolidone content of rapeseed meal and also the isothiocyanate/thiooxazolidone ratio vary considerably from sample to sample.
PRESSOR RESPONSIVENESS FOLLOWING ACUTE ELEVATION OF SODIUM IN THE RAT
Authors: Friedman Sydney M. , Webber W. A. , Jamieson J. D. , Friedman Constance L.
Published: December 2009

In order to test the effects of various ions on pressor responsiveness, groups of adult rats were infused with solutions containing sufficient sodium, potassium, calcium, or magnesium to elevate the plasma concentration of these ions. The infusions were completed within 5 minutes and in no case was more than 0.5 ml. injected. The test solutions used were sodium acetate, potassium citrate, calcium chloride, and magnesium sulphate. Control solutions of ammonium acetate, ammonium sulphate, sodium chloride, and sucrose were also infused. In no case was the amount of salt infused sufficient to affect the blood pressure during the infusion. The blood pressure response to 1 γ of norepinephrine or to 20 mU. of pitressin was recorded before infusion and again at the end of the infusion. A significant effect was observed only with sodium acetate. This consisted of a profound suppression of the ordinary pressor response to both norepinephrine and pitressin. The effect was not due to the acetate ion and hence may be specifically referable to the high plasma sodium. These results support our previous conclusions that pressor responsiveness and sodium mobility are causally connected.
STUDIES ON WHEAT PLANTS USING C14COMPOUNDS: IV. DISTRIBUTION OF C14IN GLUTAMIC ACID, ASPARTIC ACID, AND THREONINE ARISING FROM ACETATE-1-C14AND -2-C14
Authors: Bilinski E. , McConnell W. B.
Published: December 2009

Glutamic acid, aspartic acid, and threonine isolated from the gluten of wheat plants to which acetate-1-C14or -2-C14was administered during growth have been degraded to determine the complete intramolecular distribution of C14. Sixty-three per cent of the activity in glutamic acid arising from acetate-1-C14was in carbon-5 and 20% in carbon-1; glutamic acid from acetate-2-C14contained 43% of the activity in carbon-4 and about 18% in each of carbons 2 and 3. Acetate-1-C14resulted in labelling largely in the terminal carbons of aspartic acid, and acetate-2-C14preferentially labelled the internal carbons. The results show that the Krebs' citric acid cycle provides a major pathway for the biosynthesis of the dicarboxylic amino acids of wheat gluten.Striking parallelism in the intramolecular distribution of carbon-14 in aspartic acid and threonine demonstrates that these amino acids are closely linked biosynthetically and is in accord with the idea that aspartic acid provides the carbon skeleton for threonine.
THE EFFECT OF CASTRATION ON THE INCORPORATION OF ACETATE-1-C14INTO CHOLESTEROL IN THE ALBINO RAT
Authors: Dugal Louis-Paul , Saucier Guy
Published: December 2009

In male castrated albino rats the incorporation of C14from acetate-1-C14into the cholesterol of the liver, the adrenals, and the heart is significantly increased as compared to the incorporation found in the same tissues of control animals. The metabolic C14O2originating from the injected acetate is not affected by castration, nor is the total activity of the urine. There is, incidentally, a significant increase in adrenal weight following castration.
THE RELEASE OF CATECHOLAMINES FROM THE ISOLATED CHROMAFFINE GRANULES OF THE ADRENAL MEDULLA USING SULPHYDRYL INHIBITORS
Authors: D'Iorio Antoine
Published: December 2009

The influence of five sulphydryl inhibitors has been tested on isolated chromaffine granules of bovine adrenal medulla. The two mercury derivatives p-chloromercuribenzoic acid and p-choloromercuriphenylsulphonic acid exert a marked releasing activity on the catecholamines, ATP, and proteins of these granules. Three other compounds, iodosobenzoic acid, N-ethyl maleimide, and bis(2-succinylaminophenyl) disulphide, exert a similar action but to a lesser degree.Addition of glutathione to the incubation medium prevents the action of p-chloromercuribenzoic acid but does not reverse it.
THE EFFECT OF ADRENALINE, HISTAMINE, AND PITRESSIN ON THE PHOSPHORUS METABOLISM OF THE ADRENAL GLAND
Authors: Nicholls Doris , Graham Carolyn
Published: December 2009

The relative specific activity of the inorganic phosphorus of the adrenal gland of rats 2 hours after an intraperitoneal injection of inorganic P32 was increased by the administration of adrenaline, histamine, or commercial pitressin. These substances are all known to cause a depletion of the adrenal ascorbic acid. The effect on the adrenal phosphorus metabolism, like the effect on the adrenal ascorbic acid, was absent or greatly reduced in hypophysectomized rats and in rats previously treated with cortisone.In hypophysectomized rats the administration of exogenous ACTH caused an increase in the relative specific activity of the adrenal inorganic P and, again like the adrenal ascorbic acid depletion, this increase was not abolished by previous treatment with cortisone.These results, together with other observations on adrenal phosphorus metabolism previously reported for rats exposed to a cold environment, strongly suggest that the incorporation of inorganic P32 into the adrenal gland is controlled by the same factors that control the depletion of adrenal ascorbic acid. It is, therefore, concluded that the incorporation of inorganic P32 into the adrenal gland is a valid index of the activity of the adrenal cortex.
A TOXICOLOGICAL AND BIOCHEMICAL STUDY OF ω-FLUORO COMPOUNDS
Authors: Parker J. M. , Walker I. G.
Published: December 2009

A series of ω-fluoro compounds have been examined for their toxicity to mice and their ability to cause accumulation of citric acid in vivo. It was found that the toxic members did cause citric acid accumulation. Since fluoroacetate causes citric acid accumulation, it was concluded that the activity of these compounds and their effect on citric acid levels is in agreement with the hypothesis that these compounds were degraded to a fluoroacetyl derivative. The findings suggested that mice can degrade to fluoroacetate, compounds containing the following terminal radicals: amine, nitro, nitrile, thiocyanate, isothiocyanate, mercaptan, fluoride, chloride, bromide, iodide, tosylate, mesylate, 2-ketone, sulphonyl chloride, 1-alkyne, ether, substituted urea, aldehyde, and carboxyl. When compared on a molar basis several of the toxic compounds containing four or more carbon atoms were more toxic than fluoroacetate. 6-Fluorohexylamiue and 6-fluorohexanoic acid, which were representative of this type of compound, were investigated in this regard. These compounds, like fluoroacetate, were not immediately reactive but appeared to be converted to the toxic end-product more efficiently. In the dog, death from 6-fluorohexylamine was due to respiratory failure.
THE EFFECT OF MAMMARY TRAUMA ON SPAYING ATROPHY OF THE UTERUS IN THE RABBIT, GUINEA PIG, AND RAT
Authors: Höhn E. O.
Published: December 2009

Uterine atrophy following spaying was significantly reduced in 22 rabbits in which six nipples were ligated at the time of ovariectomy, in comparison with 22 controls merely ovariectomized. A possible bias in these results due to variation of relative uterine weight with body weight was avoided, as was the possible effect of pseudopregnancy.Sensitivity of uterine segments to acetylcholine was more frequent among the nipple-ligated than the control animals; but this sensitivity was not obviously associated with high individual uterine weights, and the group difference observed is of doubtful significance.No obvious effect of nipple ligation on vaginal and mammary epithelial development was observed but the large uteri of some of the experimental animals showed myometrial and some endometrial development in the uterine horns.India ink injections into four nipples per rabbit or insertion of six ligatures through the skin of the back did not significantly reduce postspaying uterine atrophy. In ovariectomized rats and guinea pigs, nipple ligation produced no effect on uterine weight in comparison with controls merely ovariectomized. In the rats, vaginal smears indicated an uninterupted anoestrus in animals of both groups, for 4 weeks following the operations.The investigators who originally described the effect of nipple ligation in ovariectomized rabbits concluded that the mechanism underlying this effect was entirely humoral. Their experiments bearing on this point are regarded as inconclusive and it is suggested here that nipple trauma may influence one of the endocrines by a nervous mechanism, this endocrine in turn acting on accessory sex organs such as the uterus.
AN EVALUATION OF TWO METHODS OF ALGESIMETRY IN HUMAN SUBJECTS
Authors: Foulks James G. , Daniel Edwin E.
Published: December 2009

The effect of analgesic drugs and placebos on experimental pain thresholds has been studied in 60 untrained and three trained human subjects. Muscle compression (cuff method) and compression of tissues overlying bone (aesthesiometer method) have been employed as pain-producing stimuli. The two methods manifest a comparable degree of reproducibility. The following coefficients of variation were obtained: (1) subject-to-subject, 80%; (2) day-today, 20%; (3) moment-to-moment, 10%.The threshold elevations produced by analgesics were small and, in most cases, not significantly greater than those obtained with placebos. Responses to various agents with each method of measurement tended to be consistent from one time interval to the next on a given test occasion. There also was a positive correlation between the simultaneous results as measured by the two different procedures in the case of agents producing significant threshold elevations. However, there was no correlation between the responses of the subjects to placebos and to analgesic agents. The majority of subjects were inconsistent in their reactions to placebos. Neither exclusion of placebo reactors nor training of subjects enhanced the accuracy of threshold reproducibility or the ability to discriminate between agents. Neither method of measurement revealed threshold changes to analgesics which were large enough to detect practical differences in the potency of various agents or in the effects of different doses of the same agent.
THE SECRETION OF IODIDE IN SALIVA
Authors: Burgen A. S. V. , Seeman P.
Published: December 2009

Iodide accumulation by the dog parotid gland continues during rest as well as during secretion. On stimulation of the gland this iodide appears as a brief transient iodide concentration that merges into a lower steady level. The amount of iodide accumulated depends on the duration of the rest period and reaches a limiting value with a half time of ~ 10 minutes. Both transient and steady state saliva/plasma concentration ratios are readily reduced by increased plasma I′ and by CIO4′. The residual iodide secretion after depression by CIO4′ behaves like iodide secretion by the submaxillary gland. This gland has no iodide concentrating system. Iodide clearance values are high and of the order of the estimated total blood flow. Evidence is presented that iodide is concentrated by the duct system and that the ducts have a very high blood flow.
THE CONVERSION OF FAT TO CARBOHYDRATE DURING EMBRYONATION OF ASCARIS EGGS
Authors: Passey Richard F. , Fairbairn Donald
Published: December 2009

While ascaris eggs developed to the vermiform stage (10 days) both lipids and carbohydrates (glycogen and trehalose) decreased in amount. During the next 15 days, in which the embryo became infective, lipids continued to decrease, but at a greater rate, whereas carbohydrate was completely resynthesized. Examination of the possible sources of the required carbon revealed that protein, non-protein nitrogenous compounds, phosphorus compounds, metabolic acids, glycerol, and volatile acids occurring in the triglycerides were not adequate and that carbon dioxide was not extensively fixed. Direct evidence for the conversion of triglyceride acids to carbohydrate was furnished by the increase in lipid-free dry weight, which corresponded closely with the increase in carbohydrate. Moreover, the amount of lipid carbon which disappeared was equal to the sum of the carbon dioxide and carbohydrate carbon which appeared, and oxygen consumption was insufficient to account for the complete combustion of lipid carbon. It was concluded that the carbon of partially oxidized fragments of fatty acids, possibly acetylcoenzyme A, was incorporated into glycogen and trehalose, and hence that ascaris eggs in this stage of their development were able to bring about a net conversion of fat to carbohydrate.
FACTORS INFLUENCING THE AMOUNT OF INSULIN EXTRACTABLE FROM BEEF PANCREAS: II. EFFECTS OF ALTERING THE EXTRACTION PROCEDURE ON THE CHANGES IN THE INSULIN EXTRACTABLE FROM AGING PANCREAS AND ON RECOVERY OF INSULIN
Authors: Labuschagne C. J. , Haessig B. K. , Wrenshall Gerald A.
Published: December 2009

Using variants of a hydrochloric acid – ethanol extraction procedure, which are described, only about one-tenth of the crude insulin extractable from beef pancreas was found to be extracted in the same way as crystallized Zinc-Insulin added to extraction fluid. An effective conjugation of most of the extractable crude insulin from beef pancreas with non-insulin factors thus appears to have occurred at least during the acid–alcohol phase of extraction. Nevertheless the mouse-convulsion method used for insulin assay proved effective in estimating the amount of this conjugated fraction of the extractable insulin following the addition either of the unconjugated Zinc-Insulin-Toronto or of the conjugated Protamine Zinc Insulin (Toronto) to the crude insulin in acid alcoholic extracts of pure beef pancreas. The phases of transient increase and progressive decrease in the insulin extractable from initially fresh beef pancreas during aging also occurred in the conjugated fraction of the extractable insulin. The proportion of this crude insulin which extracted as conjugated insulin did not change appreciably during the process of aging.The above findings support the view that the transient increase superimposed on a progressive decrease in the extractable insulin during aging of fresh pancreas are not caused by progressive changes in conjugation of insulin. The finding of similar changes with time of aging in the concentration of extractable insulin of beef pancreas when two different extraction procedures were employed, and again when two different extraction media were employed, suggests that these changes are not products of the method or materials employed for extraction.
BIOCHEMICAL PROPERTIES OF PENTASERINE (α-AMINO-δ-HYDROXYVALERIC ACID): 1. NON-AVAILABILITY OF ARGININE FROM PENTASERINE IN THE GROWING RAT
Authors: Martel Fernand
Published: December 2009

Pentaserine was fed at different levels to rats on an arginine-deficient diet and was shown to have no growth-promoting effect. This is at variance with what has been obtained in chickens where pentaserine could replace arginine partially in supporting growth.
A COMPARISON OF THE CONCENTRATION OF C14IN THE TISSUES OF PREGNANT AND NONPREGNANT FEMALE RATS FOLLOWING THE INTRAVENOUS ADMINISTRATION OF VITAMIN K1-C14AND VITAMIN K3-C14
Authors: Taylor J. D. , Millar G. J. , Wood R. J.
Published: December 2009

The C14content was determined of the livers, spleens, skeletal muscle, blood, feces, and urine of both pregnant and nonpregnant female rats and of the placentas, fetal livers, fetuses, and amnionic fluids of pregnant rats following the intravenous administration of 5 mg./kg. of either vitamin K1-C14or vitamin K3-C14. The C14concentrations of the livers of the rats given vitamin Ktwere about 24 times larger than those of animals that had received vitamin K3-C14. A fivefold difference in the same direction exists between the concentrations in the spleens of the two groups. The C14levels for skeletal muscle, blood, placenta, fetal liver, and fetal tissue were of similar magnitude regardless of whether vitamin Ktor vitamin K3was administered. Isotope dilution tests revealed that following intravenous administration of vitamin K1-C14the amount of radioactivity present as unchanged vitamin Kt-C14was 12% for fetal tissue, 59% for placenta, and 120% for the maternal liver. The dry weights of the livers of pregnant rats were larger than those of nonpregnant rats and the increase was proportional to the live weight of the pregnant rat. No significant difference could be demonstrated in the percentage of the injected dose of vitamin K1deposited in the livers of pregnant or nonpregnant rats. The same was true for vitamin K3-C14. The results of this experiment indicate that vitamin K3-C14is not concentrated in the liver of the rat whereas vitamin K1-C14is. Furthermore, it would appear that both vitamin K1and vitamin K3can pass the placental barrier of the rat.
THE MECHANISM OF DEGRADATION OF CELLULOSE BY MYROTHECIUM CELLULASE
Authors: Whitaker D. R.
Published: December 2009

A swollen cellulose was hydrolyzed by Myroihecium cellulase and the loss in weight, number-average degree of polymerization, and weight-average degree of polymerization were determined at various intervals. The loss in weight relative to the change in D.P. excludes endwise cleavage as the mechanism of hydrolysis. An approximate test for random cleavage is derived from the Beall–Jorgensen treatment of random cleavage processes and, within the limits of this test, the change in weight-average D.P. relative to the change in number-average D.P. is shown to be consistent with random cleavage.
THE EFFECT OF CERTAIN ANDROGENIC STEROIDS ON THE UPTAKE OF RADIOSULPHUR IN A HEALING FRACTURED BONE IN THE RAT
Authors: Kowalewski K. , Morrison R. T.
Published: December 2009

The uptake of radiosulphur in the fractured and intact humerus of male rats was determined in normal and in castrated animals and the ratio F/I of radioactivity of fractured (F) to intact (I) bone was calculated. Castration resulted in a significant decrease of F/I ratio, as compared with normal control rats.The effect of testosterone propionate and 17-ethyl-19 nortestosterone (Nilevar) on the S35uptake in bones was studied. Testosterone administration resulted in a slight increase of the F/I in castrated rats, but had no effect on this ratio in intact animals. Both castrated and intact rats treated with Nilevar exhibited a significant rise of S35uptake in fractured bones and, consequently, high F/I ratios. It is suggested that Nilevar has a marked effect on the synthesis of chondroitin sulphate in the collagen tissues of healing fractures, as measured by the described S35uptake technique.
CHOLINE KINASE OF RAPESEED (BRASSIGA CAMPESTRIS L.)
Authors: Ramasarma T. , Wetter L. R.
Published: December 2009

Choline kinase from aqueous extracts of Polish rapeseed (Brassica campestris L.) has been purified 25-fold by fractionation with acetone and calcium phosphate gel. The purified enzyme was relatively stable when stored frozen at neutral pH, and was active over a broad range of pH, the optimum being at about pH 8.6 – 10.0. The enzyme required Mg++ and exhibited maximum activity only when the Mg++: ATP ratio was 1:1. Phosphorylcholine, ADP, and Mn++ inhibited the activity. In addition to choline, the enzyme preparation phosphorylated dimethyl- and diethyl-aminoethanol but not ethanolamine. The choline kinase from rapeseed is similar to that from yeast except that the former does not require sulphydryl groups for activation.
THE RELATION OF DIET, HORMONES, AND TUMORS TO THE ACTIVITY OF LIVER XANTHINE OXIDASE IN THE RAT
Authors: Burton A. F. , Begg R. W.
Published: December 2009

The activity of liver xanthine oxidase and of adenosine deaminase in rats was reduced to a low value when the animals were fed a low protein diet. This did not occur in tumor-bearing animals on the same diet. The maintenance of enzyme activity in the tumor-bearing animals could not be attributed to induced enzyme formation or to alteration in hormonal control, but may be associated with an increase in purine catabolism.
BIOSYNTHESIS OF LECITHIN IN. BRAIN AND DEGENERATING NERVE. PARTICIPATION OF CYTIDINE DIPHOSPHATE CHOLINE
Authors: Rossiter R. J. , McLeod I. M. , Strickland K. P.
Published: December 2009

The radioactivity of cytidine diphosphate choline labelled with P32(CMP-P32Ch) was incorporated in vitro into the phosphatides of both hypotonic homogenates of rat brain and mitochondria prepared from isotonic sucrose homogenates. With both preparations the incorporation was increased by addition of D-α,β-diglycerides prepared enzymatically from naturally-occurring lecithins.Hydrolysis of the labelled phosphatides, followed by separation of the hydrolysis products by two-dimensional paper chromatography, indicated that most of the radioactivity was in lecithin (phosphatidyl choline). Only traces of activity were present in phosphatidyl ethanolamine and phosphatidyl serine. There was also some radioactivity in an alkali-stable fraction that was designated 'sphingomyelin'.These findings are consistent with the view that the phosphatides of brain are formed in situ from smaller molecules and that the metabolic pathways for their formation are similar to those postulated by Kennedy and colleagues for the biosynthesis of phosphatides in chicken liver.The radioactivity of CMP-P32Ch also was incorporated into the phosphatides of homogenates of rat sciatic nerve. This incorporation was greater in homogenates prepared from nerves removed 13 days after previous section. It is suggested that these and other increases, found in the in vitro labelling of phosphatides in nerves degenerating after previous section, reported elsewhere, represent an increase in the potentiality of the nerve for remyelination. These increases are associated with the increase in the number of Schwann cells in the nerve.
A NONPROTEIN CONSTITUENT OF PARATHYROID GLAND EXTRACTS
Authors: Stewart G. S.
Published: December 2009

Dinitrophenylation of a commercial parathyroid gland extract under mild conditions yielded a water-insoluble protein derivative and a water-soluble nonprotein fraction that was nondialyzable and had a pH around 3.5 in dilute salt-free solution. The latter fraction was unstable and became partially dialyzable upon standing. It would appear that the original extract consists of a firm complex between a basic protein and a large, acidic, nonprotein molecule or aggregation of molecules. There is some evidence that this fraction contains sulphur in a covalent form.
THE INTERRELATION OF THE GROWTH AND METABOLIC RESPONSES TO ANTERIOR PITUITARY GROWTH HORMONE ADMINISTRATION
Authors: Beaton George H. , Banky Hannah Z. , Haufschild Audrey M.
Published: December 2009

Doses of growth hormone which were minimal with respect to body weight increase were sufficient to produce significant alterations in liver alanine – glutamic transaminase and arginase activities and blood urea and amino nitrogen levels. The biochemical effects of the hormone appeared coincident with the body weight increase. Female rats showed a more pronounced response to growth hormone than did male rats. This sex difference was evident with respect to all of the metabolic alterations observed. Although it is not possible to state whether the metabolic alterations are direct effects of the hormone, they do take an integral part in bringing about the over-all biological effect.
THE IDENTIFICATION OF A NINHYDRIN-POSITIVE URINARY COMPONENT RECENTLY REPORTED IN HYPOPHOSPHATASIA
Authors: Fraser Donald , Lucas C. C.
Published: December 2009

In 1955, the occurrence of a hitherto unreported ninhydrin-positive substance in the urine and plasma of infants suffering from hypophosphatasia was described. Evidence published at that time and subsequently suggested that the material might be phosphorylethanolamine, but the isolation and unequivocal identification of the substance has not been reported.The present paper describes the isolation of a small amount of the previously unidentified compound from the urine of the heterozygous father of a seriously affected infant. The melting point, mixed melting point, X-ray diffraction pattern, infrared absorption spectrum, and N: P ratio establish the identity of the substance to be phosphorylethanolamine. Proof that this compound occurs in hypophosphatasia provides a logical basis for further study of the metabolic importance of this substance.
BIOCHEMICAL STUDIES ON CHLORPROMAZINE: 1. THE EFFECT OF CHLORPROMAZINE ON RESPIRATORY ACTIVITY OF ISOLATED RAT BRAIN CORTEX
Authors: Lindan O. , Quastel J. H. , Sved S.
Published: December 2009

Chlorpromazine exerts a progressive inhibitory activity (at 0.3–0.6 mM) on the respiration of brain cortex in presence of either glucose, fructose, pyruvate, or L-glutamate. A similar progressive inhibition occurs with other phenothiazine derivatives such as methylene blue and phenergan. However, chlorpromazine does not inhibit oxygen uptake in the presence of succinate. Potassium-stimulated respiration is highly sensitive to chlorpromazine, as it is markedly diminished by 0.2 mM concentration of the drug, a concentration which does not affect the unstimulated respiration. The increased inhibition of potassium-stimulated respiration is only clearly seen during the early part of the experiment.Chlorpromazine is bound by tissue constituents. At a constant concentration of chlorpromazine (0.6 mM), its inhibitory effect on cortical respiration may be abolished by markedly increasing the amount of tissue present. The inhibitory effect of chlorpromazine may be diminished by addition of plasma proteins (αβ-globulin) or by addition of heated homogenized brain, liver, or kidney. No binding occurs with polyglutamic acid, ribonucleic, and deoxyribonucleic acids, but binding does occur with certain acid dyes such as trypan red. Trypan red may be used to immobilize free chlorpromazine. When the latter drug is absorbed, however, by the nervous tissue, the addition of trypan red has no effect on the metabolic inhibitions brought about by the absorbed chlorpromazine.It is concluded that chlorpromazine resembles a large variety of narcotics and anaesthetics in its marked inhibitory effects on potassium-stimulated respiration of the brain. Its action, in vitro, however, differs from that of the narcotics in bringing about progressive, apparently irreversible, inhibitions and in its high binding power with tissue proteins. Such apparently irreversible inhibition is consistent with the conclusion that the drug, after combination with the tissue, gradually diffuses into the cell bringing about metabolic inhibitions.
BIOCHEMICAL STUDIES ON CHLORPROMAZINE: 2. EFFECTS OF CHLORPROMAZINE ON INCORPORATION INTO PROTEINS, AND BREAKDOWN OF GLYCINE-1-C14BY ISOLATED RAT BRAIN CORTEX
Authors: Lindan O. , Quastel J. H. , Sved S.
Published: December 2009

Glycine is decomposed in rat brain cortex to yield carbon dioxide. This process, in which C14O2is formed from glycine-1-C14, is markedly stimulated by the presence of 10 mM glucose, the rate of production of C14O2being increased at least threefold. The presence of succinate exercises a much smaller stimulation of C14O2formation. The addition of KCl (0.1 M) or of 2,4-dmitrophenol (0.025 mM), whilst stimulating the rate of oxygen uptake, does not increase the rate of C14O2formation from glycine-1-C14. The addition of K+tends to diminish the rate. The process of glycine-1-C14breakdown to C14O2is almost insensitive to chlorpromazine, under the given experimental conditions, until relatively high concentrations (e.g. 0.6 mM) are used. The presence of chlorpromazine, however, brings about an inhibition of the rate of glycine-1-C14incorporation into rat brain cortex proteins, an inhibition of 20% being recorded at a concentration of the drug (0.2 mM) that has little or no effect on the respiration of the brain or on the rate of breakdown of glycine-1-C14into C14O2. Glycine incorporation into brain cortex proteins is a process relatively sensitive to chlorpromazine, the magnitude of inhibition being of the same order as that brought about by amytal at similar concentrations. It is suggested that chlorpromazine brings about its effects by an uncoupling of phosphorylation from oxidation in brain cortex slices.
A "CAT AND MOUSE TEST" FOR STUDYING CHANGES IN CONFLICT BEHAVIOR
Authors: Sacra P. , Rice W. B. , McColl J. D.
Published: December 2009

A method is described for producing "conflict behavior patterns" in the cat, which is useful in studying the effect of drugs on conditioned reflexes. It yields data from which an ED50may be calculated. Comparison of four ataractic agents by this procedure demonstrates the same relative order of activity as obtained by more complicated methods.
ON THE INCORPORATION OF LABELLED ADENINE INTO THE PURINES OF THE NUCLEIC ACIDS IN THE RAT
Authors: Tomlinson R. V. , Zbarsky S. H.
Published: December 2009

Adenine labelled with C14in position 2 and with N15in positions 1 and 3 was injected intraperitoneally into rats, and the purines of the nucleic acids from the pooled viscera were isolated. The C14/N15ratios of the isolated adenine and guanine were considerably lower than that of the injected adenine, indicating that during the formation of the nucleic acid purines from the administered material there was a loss of C14relative to N15. This loss was larger for the guanine, which had a C14/N15ratio 52–67% lower than that of the injected adenine. Metabolic removal of carbon 2 of the adenine was shown further by the excretion of 22% of the injected radioactivity as respiratory carbon dioxide. Fifty-three per cent of the administered radioactivity was excreted in the urine and of this less than half was accounted for as allantoin, adenine, and urea. The C14/N15ratio of the urinary allantoin was intermediate in value between those of the adenine and guanine. The evidence obtained indicates that during the metabolic conversion of adenine to guanine the purine ring may undergo rupture at the 2 position. A possible mechanism for the reaction is presented.
EFFECTS OF OVARIAN HORMONES ON THE CONTENT AND DISTRIBUTION OF CATION IN INTACT AND EXTRACTED RABBIT AND CAT UTERUS
Authors: Daniel Edwin E. , Daniel Betty N.
Published: December 2009

The uteri of rabbits and cats have been analyzed for sodium, potassium, and chloride, usually after various preliminary treatments with estrogen and progesterone. These tissues contain less potassium (50–80 meq./kg.) than striate muscle and more sodium (75–118 meq./kg.) than other highly cellular tissues. It appears that this cation composition can be attributed in part to a relatively large extracellular fluid volume (EFV).Various methods have been used to estimate the EFV in these tissues. The radiosulphate space (in vitro) does not appear to be reliable as a measure of extracellular space. The chloride space varies, but exceeds 400 ml./kg. in all cases, and in some approaches 700 ml./kg. Inulin space (in vitro) is about 60% of the chloride space, which in turn is usually smaller than the sodium space. The chloride space appears to provide the best approximation to the EFV since its volume of distribution rarely exceeds the sodium space, and since chloride (but not sodium) can be removed completely on leaching in isotonic sucrose.Calculated cellular potassium concentrations are as high as or higher (150–210 meq./l.) than in striate muscle. Apparently the low total tissue potassium concentration is a consequence of the large EFV.Appreciable quantities of sodium (20–50 meq./l.) reside outside of the chloride space in most cases, presumably in cellular water. Furthermore, a residue of sodium remains in uterine tissue after leaching in isotonic sucrose or choline chloride. With appropriate leaching procedures, an initial rapid depletion of tissue sodium is followed by a period of relatively slow loss, indicating derivation of sodium from at least two separate tissue spaces. Equilibration in isotonic potassium chloride causes nearly complete equilibration of potassium and chloride throughout tissue water, but does not remove residual sodium, suggesting chemical binding rather than Donnan distribution as the mechanism of sodium retention.The effects of estrogen and progesterone on the concentrations of cations in uterine cells are shown to be relatively small. Estrogen causes expansion of the cellular compartment relative to the extracellular space in both rabbit and cat and decreases the concentration of cation (per liter of tissue water and per liter of intracellular fluid). Progesterone treatment, given after estrogen, interfered with the ready entrance of chloride into the cellular space of rabbit uterus exposed to isotonic choline chloride. Cat uterus was not so affected, there being very little penetration of chloride even after estrogen alone.
A COMPARATIVE STUDY OF THE EFFECTS OF MALEIC HYDRAZIDE ANDp-DIMETHYLAMINOAZOBENZENE ON RAT LIVER
Authors: Mannell W. A. , Grice H. C.
Published: December 2009

Rats receiving 2% maleic hydrazide (MH) in their diet and rats fed 0.06% p-dimethylaminoazobenzene (DAB), for periods up to 26 weeks, were compared with a control group on a stock diet. For the rats on DAB there was a decrease in body weight, in desoxyribose nucleic acid (DNA) per liver cell nucleus, and in the size of the average liver cell. There was an increase in liver weight, in DNA per liver, and in the number of cells per liver. These findings confirmed previous work with this compound. No significant changes were found in any of these measurements for the rats on MH. Pathological study revealed liver neoplasms in all animals fed DAB for 10 weeks or longer. No abnormal findings were reported for any rats on MH. The results indicate that maleic hydrazide, an antisprouting agent, does not produce any effects in rat liver similar to those caused by DAB, a known carcinogen.
STUDIES ON WHEAT PLANTS USING C14 COMPOUNDS: V. GERMINATION STUDIES WITH LABELLED WHEAT SEEDS
Authors: McConnell W. B.
Published: December 2009

Radioactive wheat seeds, obtained by injecting acetate-C14 into the stems of the parent plants, were germinated in the absence of light and nutrient and the fate of the carbon-14 was observed. Carbon respired as carbon dioxide had a higher specific activity than any of the major seed components except protein. Variations were found in the patterns by which material was transferred from the kernel to new tissue as reflected in a comparison of the activity of various components. Glutamic acid was the most active compound isolated either from the original seeds or from the new tissues. This observation, together with similarities noted in the intramolecular distribution of carbon-14 in glutamic acid of new tissue and seed residues, indicated that glutamic acid was reutilized for the biosynthesis of seedling protein. Changes in the labelling of glutamic acid during transfer to new tissue are qualitatively in accord with the idea that at least some of the amino acid is used after re-entry into the tricarboxylic acid cycle.
INFLUENCE OF VITAMIN D ON CALCIUM RESORPTION AND ACCRETION
Authors: Migicovsky B. B.
Published: December 2009

The absorption of calcium through the intestinal mucosa of the chick has been shown to come under the influence of vitamin D within 2 to 4 hours after vitamin D administration.A technique is described for the measurement of calcium accretion and resorption rates in the toe bone of a chick. The effect of vitamin D on the rates of accretion and resorption was determined, and it is concluded that vitamin D affects the accretion rate, which in turn could bring about an increase in the resorption rate per bone. It cannot be stated whether the action of the vitamin D on the bone is direct or indirect.
ABNORMALITY OF ESTROGEN METABOLISM IN HUMAN SUBJECTS WITH MYOCARDIAL INFARCTION
Authors: Bauld William S. , Givner Morris L. , Milne Ian G.
Published: December 2009

Estrogen metabolism has been investigated in male subjects with and without previous myocardial infarction. The urinary excretion of estriol, estrone, and estradiol-17β has been measured 1 day before and 4 days after intramuscular injection of estradiol-17β. The excretion of the individual estrogens resulting from the administration of estradiol was determined by subtracting preinjection values from the daily excretion following injection. The resultant values of estriol (T), estrone (O), and estradiol-l7β (D) were expressed as the following ratios:[Formula: see text]These urinary estrogen ratios were found to be significantly higher in subjects with previous myocardial infarction than in control subjects. The ratios in the infarction group were not influenced by bed rest nor by the duration of time following infarction which varied from 1 week to 2 years.
PROPERTIES OF CALF THYMUS HISTONE ISOLATED BY THREE DIFFERENT METHODS
Authors: Smillie L. B. , Butler G. C. , Smith David B.
Published: December 2009

Histone of calf thymus deoxyribonucleoprotein was isolated by three different methods: (1) Extraction from nucleoprotein solutions with dilute hydrochloric acid. (2) Extraction from cold saline nucleoprotein solutions with ethanol. (3) Salting out part of the histone, followed by removal of the nucleic acid from the remainder as an insoluble lanthanum salt. Similar yields were obtained in all cases. Measurements of fractional solubility, electrophoretic mobility, and sedimentation rate disclosed the presence of two principal components corresponding roughly to those obtained in the two stages of method (3). Alterations of one component were found to take place in aqueous solutions more alkaline than pH 4.0, resulting in the appearance of artifacts some of which sedimented more rapidly, while others sedimented more slowly, than the original material.
STUDIES ON THE ENZYMATIC HYDROLYSIS OF SARIN AND TABUN
Authors: Adie Peter A.
Published: December 2009

The enzymes which hydrolyze isopropyl methylphosphonofluoridate (sarin) and ethyl N, N-dimethylphosphoramidocyanidate (tabun) have been studied. Michaelis–Menten constants and activation energies have been estimated and enzyme stability has been studied. The distribution of the enzymes in mammalian tissues has been examined. It is concluded that from each source the same enzyme is responsible for the hydrolysis of sarin and tabun but that this enzyme shows variations from source to source. That there are mixtures of very similar enzymes, having a composition in amounts characteristic of the source, is also considered possible.
DIFFERENCES IN NITROGEN CONTENT IN EXTRACTS OF CHILLED AND NON-CHILLED TISSUES
Authors: Fedoroff S. , Altschul R.
Published: December 2009

In an attempt to elucidate the increase of growth promotion of tissue cultures by extracts obtained from tissues chilled before extraction, determinations of nitrogen content were made on (a) fresh, and chilled chick embryos, (b) extracts prepared from fresh and chilled chick embryos, (c) fresh and chilled human placenta, (d) extracts prepared from fresh and chilled human placenta.There was no difference in dry weight, nitrogen content, phosphorus content, and nitrogen: phosphorus ratio between chilled and fresh chick embryos and chilled and fresh human placenta. There was, however, a significant difference in the nitrogen content of the extracts prepared from fresh and from chilled tissues, It is suggested that chilling of tissues for 7 days at + 4 °C. prior to extraction may render the cells more easily destructible during extraction, and thus supply a better yield of nutritive substances.
THE BIOSYNTHESIS OF CELL WALL CARBOHYDRATES: IV. FURTHER STUDIES ON CELLULOSE AND XYLAN IN WHEAT
Authors: Neish A. C.
Published: December 2009

D-Glucose-1-C14, D-glucose-6-C14, D-mannose-1-C14, D-galactose-1-C14, D-glucuronolactone-1-C14, D-glucuronolactone-6-C14, potassium D-gluconate-6-C14, and L-arabinose-1-C14 were administered to wheat shoots. The cellulose and xylan were isolated after a 5 hour period of metabolism. Glucose was more readily converted to cellulose and xylan than any of the other compounds tested. The distribution of C14 in the glucose and xylose isolated from the polysaccharides indicates that xylan was formed from the aldohexoses and glucuronolactone by processes involving loss of carbon-6. L-Arabinose, unlike D-xylose and D-ribose, was converted to xylan with little rearrangement of the pentose skeleton.