bluuebunny/crossref_metadata_2025 huggingface dataset:
Anterior pituitary control of active sodium transport across frog skin
Authors: Myers R. M. , Bishop W. R. , Scheer B. T.
Published: December 2017

Removal of the anterior lobe of the pituitary from the frog Rana pipiens is followed by an increase in the outflux of Na22 across the skin, which persists at least 4 months, and by a decrease in resting potential and sodium (‘short-circuit’) current, which persists no more than 3 weeks. The increased outflux is interpreted as resulting from increased permeability of the skin to sodium ion, and the decreased sodium current is interpreted as a decreased rate of active sodium transport. Either change is opposed by treatment with mammalian ACTH or with aldosterone. Effects of other hormones could not be established with certainty. The increased permeability of the skin to sodium appears to be associated with a decrease in the amount of a mucopolysaccharide in the dermis. The evidence suggests that the pituitary effects involve the interrenal bodies.
Interrenal control of active sodium transport across frog skin
Authors: Bishop W. R. , Mumbach M. W. , Scheer B. T.
Published: December 2017

Destruction of the interrenal tissues of frogs is followed by a marked decrease in active sodium transport across the isolated skin, measured electrically or isotopically, and by an increase in the electrical resistance of the skin. These values are partly but not completely restored by treatment with mammalian adrenal cortex extract, hydrocortisone, or aldosterone; ACTH is ineffective. Frogs did not survive destruction of the interrenal tissue more than 10– 14 days even if salt and glucose were administered.
Intestinal absorption of L-phenylalanine in vitro
Authors: Spencer Richard P. , Samiy A. H.
Published: December 2017

When initially present at the same concentration on both sides, net transport of L-phenylalanine by everted hamster intestinal sacs reached a steady state at 1 hour. The net amount transported, as a function of the final mucosal concentration, was described by a Langmuir adsorption isotherm. An equation was derived showing that the concentration gradient also obeyed such a formulation. Sacs from the midintestine transported more L-phenylalanine than proximal and distal end sacs. Lineweaver-Burk plots of the concentration gradient against final mucosal concentrations showed the process in end sacs to have the same KM (1.8 x 10–3 M) as that in midintestinal sacs; those from midgut, however, had a greater capacity. L-Phenylalanine absorption likely occurs by different amounts of the same mechanism throughout the small intestine. High concentrations of L-phenylalanine resulted in a depression of net transport. The importance of the concentration gradient in revealing the fall in net transport in this and other systems was stressed. l-Phenylalanine transport was also depressed by L-tryptophan and L-methionine.
Parotid secretion of rubidium
Authors: Langley L. L. , Brown R. S.
Published: December 2017

Parotid secretion of rubidium has been studied and compared with secretion of potassium. Potassium is rapidly transferred by the duct cells of the parotid gland from the plasma to the saliva. The concentration in a series of two-drop saliva samples reaches a peak in about the sixth sample after which the concentration is maintained characteristically high. In contradistinction, other ions display a rapid decrease in concentration. Rb86 shows a curve similar to that of potassium. Potassium and rubidium respond identically to changes in saliva flow rate. At flow rates of 0.2 or 0.3 ml/min. the concentration of both ions in the saliva is approximately twice that of the plasma. The S/P ratio progressively increases with decreasing flow rates reaching a maximum of about 8 at a saliva flow of 0.01 ml/min. Elevation of the plasma concentration of both ions evokes an increased saliva concentration. It is concluded that rubidium is transferred from plasma to saliva by the duct cells of the parotid gland and is transported by the same mechanism responsible for potassium secretion.
Effect of dietary fat on metabolism of cholesterol-26-C14 in the rat
Authors: Ferguson Harold A. , Coniglio John G. , Blood Frank R.
Published: December 2017

Rats were maintained for varying periods of time on a purified diet containing 20% fat as hydrogenated cottonseed oil, corn oil or coconut oil and then injected intravenously with a tracer dose of cholesterol-26-C14 in solution. No significant influence was observed by the type of fat ingested on the amount of C14 converted to C14O2, excreted in feces, or retained in the nonsaponifiable fraction of several selected tissues. From 9 to 17% of the administered dose of C14 was expired as C14O2 and from 3 to 8% was excreted in feces in 72 hours. The greatest amount of C14 retained in the body was found in the liver (11–22%), and in this organ the largest values were observed in those animals which had been on the diet the shortest length of time.
Vitamin B12-intrinsic factor studies with isolated perfused rat liver
Authors: Toporek Milton
Published: December 2017

Vitamin B12-intrinsic factor relationships have been studied with the isolated perfused rat liver technique. Approximately 20 times more vitamin B12 is absorbed by the liver in the presence of intrinsic factor than without it. Rapid and significant transfer of vitamin B12 from liver to bile has been observed. The dose-response curve for this system is similar to that reported for the absorption of vitamin B12 through the intestinal tract of pernicious anemia patients. The order and time of addition of vitamin B12 and intrinsic factor to the perfusing blood is critical for absorption of vitamin B12 by the liver. If vitamin B12 is added first, binding substances in the blood rapidly make vitamin B12 unavailable to intrinsic factor added subsequently. If intrinsic factor is added first, gradual inactivation or removal of intrinsic factor by the liver leads to a much slower decrease in efficiency of absorption of subsequently added vitamin B12. These effects are similar to those reported on absorption of vitamin B12 through the human intestinal tract.
Distribution of nonelectrolytes in muscle
Authors: Bozler Emil
Published: December 2017

Uptake and rate of efflux of some nonelectrolytes was studied in stomach muscle and sartorius of the frog. After complete equilibration the concentration in muscle water approximated that of the medium for glycerol, but was higher for urea and thiourea. Erythritol space averaged 50%. d-Arabinose and sucrose distributed themselves in a smaller volume, which, however, was always greater than that of inulin. Efflux of sugars did not follow first-order kinetics and became very slow after a few hours. This was true also for muscles washed in formalin. In glycerol-extracted muscle fibers, sucrose space was nearly as large as water space, but inulin space was significantly lower. It is concluded that sugars and some other nonelectrolytes penetrate into the fibers but are excluded from part of the intracellular water and, therefore, produce osmotic effects. The results support the hypothesis that most of the fiber water is contained in segregated or narrow spaces, hindering diffusion of all except very small molecules.
Temperature regulation of rats with hypothalamic hyperphagia
Authors: Han Paul W. , Brobeck John R.
Published: December 2017

Temperature regulating mechanisms of rats with ventromedial lesions of the hypothalamus were studied by determining their body temperature responses to exercise, and to exposure to cold or heat. These lesions caused no primary impairment of temperature regulation. A higher body temperature observed after forced exercise was found to be secondary to the rats' hyperphagic behavior and their consequent weight gain.
Transient increase in blood sugar following experimental pancreatitis
Authors: Bridgwater Anna B. , Ogawa T. , Chiles T. , Necheles H.
Published: December 2017

A transitory hyperglycemia was observed after production of bile pancreatitis in the dog. This phenomenon was characterized by an immediate increase in blood sugar after injection of bile, reaching a maximum at 10–30 minutes and returning to or near normal values within 45–90 minutes. Substances other than bile, particularly vegetable oils, also produced this reaction. It was not changed significantly in adrenalectomized animals or in those pretreated with dihydroergotamine, but in cobalt-treated dogs the response was almost completely prevented. Epinephrine from the adrenals appears to be ruled out as the major causative factor, whereas glucagon is implicated. Dihydroergotamine did not completely block hyperglycemia following epinephrine in the dog under the conditions of our experiment.
Chicken prothrombin, thrombin, and fibrinogen
Authors: Bigland C. H. , Triantaphyllopoulos D. C.
Published: December 2017

Avian blood coagulation studies revealed the mean one-stage prothrombin time of plasma from 100 chickens, 10 weeks of age, as determined with chicken brain thromboplastin, to be 11.4 seconds, compared with 10–300 seconds found by other workers; the mean prothrombin content was 137% of human prothrombin levels, as determined by the one-stage prothrombin-time technique, but only 53% by the adsorption and elution technique used. Fibrinogen determinations on the same plasma revealed a mean of 346 mg/ 100 ml of plasma, compared with 250–400 for humans. Chicken thrombin was prepared which gave a mean thrombin time on the same, but buffered, plasma of 12 seconds. Coagulation of chicken plasma with chicken thrombin was found to be highly sensitive to variations in pH, being 12 seconds at pH 7.1, but lengthening to over 60 seconds at pH 7.7. Greatly increased clotting times of chicken plasma with bovine thrombin and with rabbit thromboplastin indicated evidence of species specificity.
Utilization of acetate-1-C14 by hepatic tissue from cold-exposed and hibernating hamsters
Authors: Denyes Arliss , Carter Joan D.
Published: December 2017

When the hamster is exposed to cold (6 ± 1 C), there is a profound block in hepatic lipogenesis from C14-acetate within 48 hr. By 8 weeks of cold exposure this block has been repaired to 74% of the control value. During hibernation, which generally occurs after the 8th week, a block in lipogenesis is again present. By 6 hr of arousal, the degree of lipogenesis has been either slightly repaired or has returned almost to the 8-week level. Accompanying this block in lipogenesis is an increase in the production of C14O2 from C14-acetate in animals exposed to cold. In vitro addition of .02 m glucose did not stimulate lipogenesis in hepatic tissue of cold-exposed hamsters, except for a few of those animals aroused from hibernation for 6 hr. Addition of .02 m succinate in vitro did not increase lipogenesis or C14O2 production from C14-acetate. Fructose repaired the hepatic lipogenesis in all groups of cold-exposed hamsters. It was concluded that the cold-exposed and hibernating hamster has biochemical lesions involving the glucokinase reaction and some other step in the glycolytic pathways of the liver.
Effects of glucose on palmitate esterification by isolated rat diaphragms
Authors: Fritz Irving B. , Kaplan Eli
Published: December 2017

The uptake of palmitate -1-C14 and its conversion to various products by hemidiaphragm preparations incubated for 2 hours was measured in the presence and absence of added glucose or insulin. Following glucose and insulin addition, oxidation of palmitate to CO2 by muscle obtained from either fed or starved rats was decreased, and incorporation of palmitate into neutral lipids freed of unesterified fatty acids was enhanced. The data indicate that the glucose sparing action on fatty acid oxidation by isolated muscle is related to stimulation of glyceride synthesis. Insulin alone was without effect on palmitate metabolism, but insulin addition in the presence of glucose accentuated the glucose sparing action. The data are discussed in relation to the overall effects of glucose on lipid metabolism in vivo, and possible sites of action of glucose on the stimulation of net glyceride synthesis are considered.
Metabolism of glucose-1-C14 and glucose-6-C14 by liver slices of refed rats
Authors: Tepperman Jay , Tepperman Helen M.
Published: December 2017

Rats starved for 48 hours and refed a high carbohydrate diet show an increase in hepatic lipogenesis and a marked increase in activity of the enzymes of entry into the HMP shunt. An analysis is given of the patterns of glucose-1-C14 and -6-C14 metabolism in liver slices of refed rats. At 24 and 48 hours the ratios of carbons 1 and 6 in both CO2 and lipid are consistent with an increase in glucose metabolism via the direct pathway, especially in view of the previous finding of elevated HMP dehydrogenase activity under these conditions. In addition, a description is given of the temporal relationships of glycogen deposition, lipogenesis recovery, and differentially labeled glucose metabolism in the first 12 hours of refeeding.
Calcium clearance as a function of sodium clearance in the dog
Authors: Walser Mackenzie
Published: December 2017

During diuresis induced in dogs by water, sodium chloride, sodium bicarbonate, mannitol, glucose, or sucrose, the plasma calcium clearance is, on the average, half the sodium clearance. Free calcium ion clearance therefore equals sodium clearance. This relationship is not altered by reducing calcium or sodium intake, by varying urinary flow or urinary ionic strength, or by varying chloride excretion, independently of sodium excretion. It is only slightly affected by urinary pH, and is not distinctly altered by potassium infusion. Sodium and calcium ions are thus reabsorbed in the proportions in which they are present in plasma. However, previous observations made during sulfate diuresis, when approximately half of the urinary calcium is complexed by sulfate, suggest that the tubular cells tend to maintain a constant ratio of sodium to free calcium ions in the tubular fluid, rather than to reabsorb proportionate quantities of each. It is speculated that this may reflect competitive binding of calcium and sodium at the cell membrane.
Compensations of cardiac output and other circulatory functions in areflex dogs with large A-V fistulas
Authors: Guyton Arthur C. , Sagawa Kiichi
Published: December 2017

In ten dogs made areflex by administration of total anesthesia, opening large A-V fistulas with flows equal to the control cardiac output caused an instantaneous average increase in cardiac output of 75%. Obviously, therefore, the circulation can compensate for most of the fistula flow in the complete absence of all circulatory reflexes. In the same number of animals with intact reflexes, the compensation was 82%. Most of the compensation in both the areflex and the reflex dogs occurred literally with the next few heartbeats after opening the A-V fistulas, though, in the animals with the intact reflexes, an additional small degree of compensation occurred during the ensuing 15–30 sec; this additional effect was ascribed to reflexes. The nonreflex portion of the compensation can be explained by a) increased venous return caused by decreased peripheral resistances and b) cardiac adaptation in accordance with Starling's principle.
Effects of hormones and hypoglycemic agents on testicular fat in the rat
Authors: Smith T. C. , Will L. , Oleson J. , Benitz K. -F. , Perrine J. , Ringler I.
Published: December 2017

Response of transplanted and nontransplanted fat bodies to various hormones, tolbutamide, and hypoglycin A was compared by measuring the amount of lipids in the dissected fat bodies after 2 weeks treatment. Simultaneous measurements of food intake and body weight were made to serve as a basis for evaluating the effects on fat. Protamine zinc insulin produced an increase in lipid content of the testicular fat body, accompanied by elevation in food intake in three of five experiments; hydrocortisone acetate, triamcinolone or its 16,21-diacetate, or diethylstilbestrol brought about decreases in lipid with either no change or a decline in food intake; epinephrine·HCl or growth hormone elicited decreases in lipid without significantly influencing food intake or body weight. Generally, transplanted fat was more responsive to these agents than the undisturbed fat body. Both tolbutamide and hypoglycin A decreased lipids in the transplant without affecting those in untransplanted fat. Food intake, body weight, and blood glucose were not changed.
Separation of insulin effects on K content and O2 consumption of frog muscle with cardiac glycosides
Authors: Gourley D. R. H.
Published: December 2017

Digoxin, deslanoside, or ouabain, in concentrations ranging from 10–9 to 10–4 m, caused a net loss of potassium from isolated intact frog skeletal muscle in the presence of lactate as substrate. The glycosides in concentrations of 10–7 to 10–4 m had little or no effect on oxygen consumption, and the stimulation of oxygen consumption by insulin was not affected by the addition of 1 µm of any of the glycosides. However, the insulin stimulation of potassium uptake by the muscle was completely blocked by digoxin and almost completely blocked by deslanoside. Insulin and ouabain together caused a greater net loss of potassium than did ouabain alone. Although the mechanisms of these effects on muscle potassium by insulin-glycoside combinations are not fully understood, a possible interpretation is that insulin acts on at least two separate sites in skeletal muscle, the potassium transfer system, and the lactate oxidation mechanism, only the first of which is influenced by cardiac glycosides.
Effect of cardiac glycosides on blood volume of the dog
Authors: Cotten Marion deV. , Williams Betty J.
Published: December 2017

The effects of cardiac glycosides on plasma volume, extracellular water volume, hematocrit reading, concentrations of hemoglobin and plasma proteins, and calculated blood volume were determined in both conscious and anesthetized dogs. The administration of 40% of the fatal dose of a cardiac glycoside had no statistically significant effects upon any of the parameters measured which could be ascribed to direct vascular actions of the drug. Thus, the plasma and extracellular water volumes were generally unaffected by either the injection of a cardiac glycoside or its solvent. In several experiments with conscious dogs, however, plasma volume decreased after injection of a glycoside apparently due to the development of severe vomiting. Hematocrit readings and hemoglobin concentrations were frequently moderately elevated after injection of a glycoside in normal dogs. The latter changes were apparently due to glycoside-induced splenic contraction, since they were absent in splenectomized dogs. It is concluded that the decrease in cardiac output caused by cardiac glycosides in normal dogs is not the result of a decrease in blood volume.
Regulation of blood glucose concentration: hepatic action of insulin
Authors: Leonards Jack R. , Landau Bernard R. , Craig James W. , Martin F. I. R. , Miller M. , Barry Frank M.
Published: December 2017

Insulin was administered intravenously with or without the concurrent infusion of glucose to dogs surgically prepared so that hepatic glucose production could be measured directly. In dogs fed a high protein diet, hepatic glucose output as directly measured did not significantly change on insulin administration. The threshold at which a net hepatic glucose uptake occurred on the administration of a glucose load was unaffected by the presence of insulin. In contrast, in dogs fed a high carbohydrate diet, on the simultaneous infusion of insulin and glucose, a net uptake of glucose by the liver occurred at lower than normal plasma glucose concentrations. Hepatic glucose production was also estimated indirectly by isotopic techniques. A brief decrease in the rate of decline of plasma glucose specific activity was observed following the injection of C14-labeled glucose and then insulin in both protein and carbohydrate-fed animals. The explanation for this phenomenon remains uncertain. It is concluded that dietary status is important in determining the action of insulin on the liver. In dogs fed a high carbohydrate diet an almost immediate and perhaps direct action of insulin on the liver appears demonstrable.
Continuous light or darkness and circadian periodic mitosis and metabolism in C and D8 mice
Authors: Halberg Franz , Barnum Cyrus P.
Published: December 2017

In immature C mice exposed first to alternating 12 hr of light and 12 hr of darkness (LD), and maintained thereafter in constant darkness for several days, the circadian rhythms in hepatic and pinnal mitosis are demonstrable by spot checks made at the approximate times of LD-synchronized peak and trough. Spot checks at same times in mice of same stock and age, kept for several days in constant light, reveal the cell division rhythm of liver parenchyma, but not that of pinnal epidermis. In immature D8 mice kept for several days in constant darkness, rhythms in hepatic mitosis, phospholipid, ribonucleic and deoxyribonucleic acid metabolism persist, while cell division rhythm in ear pinna of same animals is not detectable with the particular spot check used. In mice of same stock and age, on the 4th day in constant light, a significant rhythm persists in the relative specific activity of the hepatic phospholipid; timing of this metabolic cellular rhythm is drastically desynchronized from the reference standard of a 24-hr clock. Data reveal persistence of some mitotic and metabolic circadian rhythms under conditions studied, with phase drifts or phase shifts of these rhythms occurring both in relation to the 24-hr clock and among the rhythms themselves. These changes in external and internal timing of a circadian system are more extensive in constant light than in constant darkness.
Effect of growth hormone on conjugation of ingested glycine with aromatic acids
Authors: Gaebler O. H. , Choitz H. C. , Kurrie Dorothy
Published: December 2017

Benzoate or phenylacetate was added to the food of normal adult bitches to bring about biosynthesis of hippuric or phenaceturic acid at a rate which, for each acid, was comparable in experiments with and without growth hormone. Utilization of ingested N15-labeled glycine for these syntheses was determined in control experiments and in growth hormone experiments at the time of maximal nitrogen storage induced by treating the same animals with 5 mg of hormone daily for 4 days. The total amount, as well as the amount per mole, of labeled glycine incorporated into hippuric acid was greater in growth hormone than in control experiments throughout a 72-hr period of observation. During the first 6 hr after ingestion of labeled glycine, the rate of its incorporation into phenaceturic acid was also increased by growth hormone, but the total amount utilized for this synthesis in 72 hr was unaffected. A previously demonstrated effect of growth hormone on utilization of N15 from glycine for purposes other than synthesis of hippuric or phenaceturic acid was not prevented or notably reduced by feeding benzoate or phenylacetate.
Precocious ovarian stimulation following interruption of stria terminalis
Authors: Elwers Mildred , Critchlow Vaughn
Published: December 2017

To study the effects of interruption of stria terminalis on ovarian activity in immature rats, bilateral electrolytic lesions were placed in 69 female Holtzmann rats at 18–20 days of age; 41 nonoperated littermates served as controls. All animals were killed at 33 days of age and the endocrine organs and uteri were weighed. Brains were serially sectioned and examined histologically for lesion localization. Seventeen rats with bilateral interruption of stria terminalis had a mean uterine weight of 146.1 ± 13.60 mg compared with 85.3 ± 4.38 mg for the controls ( P < .01). Although the vaginas of all control rats remained closed, five rats with bilateral transection of stria terminalis had open vaginas prior to autopsy. Similar stimulatory effects were not observed with bilateral lesions of thalamus, caudate-putamen, fimbria of the fornix or internal capsule. The results support the inclusion of the amygdaloid complex in neural mechanisms that inhibit gonadotrophin secretion in the immature female rat and suggest that the influence of the amygdala is mediated primarily through the stria terminalis.
Characterization of the metabolic gradient in cat small intestine by layer fractionation
Authors: Dorman H L. , Steggerda F. R.
Published: December 2017

Gradations in oxygen consumption were observed in preparations of intact segments and in layer fractions of cat small intestine, which were excised following Nembutal anesthesia. Mechanical separation of the intestinal segments into layers provided a means for localization of these gradients within specific components of the intestinal wall. Gradients were found in segments of the submucosal and mucosal layers and in segments composed of circular muscle, submucosa, and mucosa; but none was observed in segments of the isolated circular muscle layer. Inactivation of one or both intrinsic ganglionic plexuses by mechanical separation abolished the gradient associated with the circular muscle layer. The tentative explanation of these findings is that the existence of a metabolic gradient within the intestine arises from two sources: a) a graded activity within the submucosal mucosal layers and b) a sharply graded differential oxygen consumption within the muscular layers which is controlled by the functional activity of the intrinsic ganglia.
Effects of brain extracts on activity of the trigeminal motor and hypoglossal nuclei
Authors: Kawamura Yojiro , Funakoshi Masaya , Takata Mitsuru
Published: December 2017

Alterations in trigeminal motor and hypoglossal nuclei discharges were noted following microinjections of ethanol and saline brain tissue extracts, ACh and γ-aminobutyric acid (GABA). Background activities of these nuclei were not affected by microinjection of 0.9% saline solution or tris buffer [tris (hydroxymethyl) amino methane] of pH 7.2. Solutions of pH 8.5 (tris buffer) or pH 5.8 (glycine buffer) gradually inhibited these discharges. Spontaneous discharges of the trigeminal motor nuclei were accelerated by the saline extract of the brain tissue and ACh, and they were inhibited by the ethanol extract of the brain tissue and GABA. Discharge of this nucleus accelerated by lower jaw depression was also inhibited by the ethanol brain extract and GABA. Background activity of the hypoglossal nuclei was mildly accelerated by the saline brain extracts and ACh, greatly accelerated by the ethanol brain extracts, and strongly inhibited by GABA. The saline extract of the brain tissue extracted from brain stem had a stronger activator than that extracted from cortical tissue.
Shifts in fluid and protein with overtransfusion and hemorrhage in the dog
Authors: Smith E. L. , Deavers S. , Huggins R. A.
Published: December 2017

After control determination of red cell and plasma volume and protein concentration, seven dogs were successively overtransfused with a mean of 90 cc/kg blood, then slowly hemorrhaged to an arterial pressure of 35 mm Hg and, finally, the blood reinfused. Red cell and plasma volume and protein concentration were determined after each procedure. The bleeding volume of overtransfused dogs was larger by 11% than it was in a previously published series of dogs. However, the fraction of blood remaining in the vascular system after hemorrhage, expressed in percentage of the prehemorrhage volume for overtransfused and control dogs, was approximately the same, 66 and 61%, respectively. After the hemorrhage of overtransfused dogs, 4.6 cc/kg fluid and 2.7 g% protein left the circulation, whereas, for the control series considerable amounts of protein and fluid entered the circulation. On reinfusion, 13.9 cc/kg fluid and 4.7 g% protein left the circulation of the overtransfused dogs, a phenomenon which occurs to an even greater extent in the control group.
Effect of aging on lipid composition and metabolism in the adipose tissues of the rat
Authors: Benjamin William , Gellhorn Alfred , Wagner Mary , Kundel Harold
Published: December 2017

Lipid metabolism and chemistry was studied in adipose tissues of the rat from the age of 38 days to 647 days. Aging process was characterized by a marked decrease in lipid synthesis from acetate, a reduction in the proportion of glucose metabolized by the pentose phosphate pathway, and a lower rate of palmitate incorporation into the mixed lipids. Oxidation of palmitic acid to CO2 and release of free fatty acid by epididymal fat was the same in young and old tissues under control conditions; when, however, glucose was absent from the medium or when epinephrine was added, there was a significantly greater rate of palmitic acid oxidation and free fatty acid release by young compared to old adipose tissue. Rate of acetate incorporation into mixed lipids by multiple adipose tissue sites was determined at different ages. Consistently greater rates of lipid biosynthesis were found in the epididymal, perirenal, mesenteric and interscapular adipose tissues than in subcutaneous fat at all ages. Rate of lipid synthesis by the interscapular fat (unlike any of the other depots) remained high at all ages studied. A greater proportion of short chain fatty acids was found in adipose tissues from young rats than in the old. This was related to fatty acid composition of rat milk.
Relationship between food and water ingestion in the rabbit
Authors: Cizek Louis J.
Published: December 2017

Studies of ad libitum food-water intake relationship were made on 146 rabbits over a period of 7 1/2 years. Fluid intake was considerable, averaging at least 200 cc/day. Though daily variations occurred, major deflections from this mean were rare. Six-month studies revealed a quantitative linear relationship between food and water intakes. This relationship was altered somewhat by age since both water and food intake continue to decrease with time, water at a slightly greater rate than food. When food was suddenly removed, male rabbits consistently displayed a syndrome of polydipsia and polyuria. Balance studies revealed a sodium chloride deficiency. This caused polydipsia because substituting saline for drinking water abolished enhanced drinking. Equimolar solutions of potassium chloride were without such an effect. Female rabbits showed variable responses to food deprivation, depending on age. When young, the response was polydipsic. Repeated food deprivations resulted in decreasing responses as the rabbit matured; as aging continued, the responses reverted back to a polydipsic phase. Castration of females abolished this cyclic response.
Protoporphyrin and heme formation by erythrocytes from the x-irradiated and bled duck
Authors: Klein J. Raymond
Published: December 2017

Frequent bleeding of the adult, male duck was followed by increase in protoheme and free protoporphyrin formation by erythrocytes in vitro. X-irradiation of the animal with 800 or 1,200 r was followed by decrease in heme formation but not in free porphyrin production. Heme formation was not limited by the natural supply of porphyrin precursors and iron in blood and appears to be controlled by the uptake of iron by the cells. Free porphyrin production does not appear to be regulated by heme formation.
Regulation by sympathetic nervous system of accelerated growth of salivary glands of rats
Authors: Wells Herbert , Handelman Chester , Milgram Elliot
Published: December 2017

Although the early (24-hr) effect of unilateral extirpation of the superior cervical sympathetic ganglion is to increase the weight of the submandibular salivary gland on the operated side, ganglionectomy subsequently results in an inhibition of the normal growth of the ipsilateral submandibular gland, evident within 8 days. Prior ganglionectomy almost completely prevents the increase in weight of the ipsilateral gland which otherwise follows either amputation of the lower incisor teeth or resection of the inferior alveolar nerve. The increase in gland weight which follows a single amputation of the incisors was significantly inhibited in rats treated with reserpine or bretylium tosylate, drugs which interfere with the storage or release of norepinephrine by sympathetic nerves. It is concluded that these data support the hypothesis previously offered that the sympathetic nervous system may be involved both in the accelerated growth of the submandibular glands that follows amputation of the lower incisor teeth and in the maintenance of normal salivary gland size.
Effects of GFR and renal plasma flow on urine osmolarity
Authors: Abbrecht Peter H. , Malvin Richard L.
Published: December 2017

The effects on total urine osmolarity of renal plasma flow rate (RPF) and glomerular filtration rate (GFR) were determined in dogs during mannitol diuresis. While one kidney served as a control, RPF and GFR in the other kidney were varied by one of the following methods; A—Partial occlusion of the ureter. This decreased GFR with negligible decrease in RPF. B—Partial occlusion of the renal artery. This decreased both GFR and RPF simultaneously. C—A combination of partial ureteral occlusion and partial occlusion of the renal artery to obtain reductions in GFR and RPF other than those attained by methods A or B. GFR was determined by creatinine clearance and RPF by the Fick principle using the renal A-V difference for PAH. Graphical correlations were obtained relating urine osmolarity to GFR and RPF. The data show that the RPF has an important independent effect on urine osmolarity in addition to its indirect action through its effect on GFR.
Histochemical localization of glutaminase I activity in kidney
Authors: Karnovsky Morris J. , Himmelhoch S. Ralph
Published: December 2017

A histochemical method is described for the demonstration of glutaminase I in sections of fresh frozen tissue cut in the cryostat. The application of this method to the kidney of the golden hamster revealed extremely high activity of glutaminase I in the papillary collecting ducts, where ammonia is known to appear in the urine. High activities were also present in other segments of the hamster nephron. In the normal and acutely acidotic rat, only slight glutaminase I activity was present in the papillary collecting ducts, although the descending limbs of Henle's loop were quite active. Other segments of the rat nephron, both normal and acidotic, possessed glutaminase I activity. A generalized increase in activity was observed in acidotic animals.
Renal hemodynamics during hyperthermia caused by exposure to high environmental temperature
Authors: Kanter G. S.
Published: December 2017

The GFR (glomerular filtration rate) and RPF (renal plasma flow), following an initial increase, fell significantly after 3–4 hr exposure of anesthetized dogs to an air temperature of 49 C. This alteration occurred with either dehydration or hydration present. Creatinine clearance was used as a measure of GFR and p-aminohippuric acid clearance at low plasma levels was used as a measure of RPF. Rectal temperature averaged 43 C at the conclusion of the experiment. The hematocrit increased 14%. The alteration in renal hemodynamics was shown to be due to a mild fall in mean systemic blood pressure, and a concomitant early decrease in intrarenal resistance followed a further decrease in blood pressure, combined with a progressively increasing intrarenal resistance. It can be concluded that while the fall in blood pressure, increasing intrarenal resistance during the latter part of the exposure, and decreased GFR and RPF are resultants of hyperthermia, the massive loss of plasma volume and increase in hematocrit previously reported in hyperthermia produced with heating pads (largely conductive heating) need not occur. Such major changes may be ascribed to tissue damage rather than to hyperthermia, per se.
Production of diabetes insipidus in hypophysectomized rats by hypothalamic lesions
Authors: Gale C. C. , Taleisnik S. , McCann S. M.
Published: December 2017

Lesions in the median eminence produced permanent diabetes insipidus (DI) in chronically hypophysectomized rats. Water turnover in these animals, however, was only about half of that observed when lesions were made in rats with intact pituitaries and was further characterized by absence of the normal interphase. Conversely, when hypophysectomy was performed in rats with DI, an immediate and sustained 50% reduction in water intake occurred. Administration of adrenocorticotropin to hypophysectomized rats with lesions caused significant augmentation of DI, but not to levels found in rats with DI and intact pituitaries. Neither somatotrophic hormone (STH) nor triiodothyronine increased water turnover when given to hypophysectomized animals with DI. Lesions in the median eminence of hypophysectomized rats induced an immediate increase in urine volume in the absence of water intake, which indicates that primary polyuria was responsible at least in part for the development of DI in hypophysectomized rats with lesions.
Epinephrine-insulin antagonism on free fatty acid release
Authors: Spitzer John J. , McElroy William T.
Published: December 2017

The effects of epinephrine or norepinephrine were studied in dogs receiving insulin plus glucose prior to and during administration of the amine. Epinephrine caused a significantly smaller elevation of free fatty acids (FFA) with than without insulin plus glucose administration. Blood sugar responses were quantitatively similar. Epinephrine increased both hepatic uptake of FFA and hepatic release of glucose; these changes were similar to the ones found previously in dogs not receiving insulin plus glucose. The action of norepinephrine on elevating plasma FFA was only slightly and not significantly affected by the administration of insulin plus glucose. When the order of drug administration was reversed, infusion of insulin plus glucose lowered plasma FFA levels and hepatic FFA uptake in animals already receiving either epinephrine or nonepinephrine.
Effect of thalamic lesions on spontaneous electrical activity in MES auditory cortex
Authors: Tunturi Archie R.
Published: December 2017

Standard deviations (sd) and spatial correlation coefficients ( r) of spontaneous electrical activity were computed for multiple locations on the surface of the middle ectosylvian auditory area of the dog, before and after lesions in the white matter under the area, thalamus, midbrain, and medial geniculate body. Locally applied cocaine decreased sd and increased r between locations greater than 6 mm apart from 0.3–0.5 to values > 0.75. Immediate subcortical aspiration after cocaine had no effect on sd or r, but after recovery from the cocaine, sd returned to normal and r was depressed (< 0.3–0.5) between distant locations. Lesions of the medial geniculate body decreased sd but had little effect on r. Large lesions of the thalamus produced significant decreases in r but only a moderate number of changes in sd. Lesions of the latera lemniscus caused moderate changes in sd and r.
Chick embryo heart as a tool for studying cell permeability and insulin action
Authors: Guidotti Guido , Kanameishi Doris , Foà Piero P.
Published: December 2017

Glucose uptake by chick embryo hearts at various stages of development was measured in aerobic and anaerobic conditions, with or without the addition of insulin. Glucose uptake per gram of tissue decreases as the age of the embryo increases. Increasing the concentration of glucose in the medium causes an increase in uptake by 5-, 7- and 9-day-old hearts; a plateau is reached only with 5-day-old hearts. Anoxia stimulates glucose uptake at all ages studied; insulin has no effect in 5-day-old hearts, but stimulates glucose uptake in hearts 7 days old or older. The results of these experiments suggest the following conclusions: 1) The 5-day-old chick embryo heart is permeable to glucose and, in this preparation, glucose uptake is limited by the rate of intracellular phosphorylation. 2) During the 7th day of embryologic development, coincident with the first production of beta granules in the pancreas of the embryo, an insulin-sensitive "membrane" regulating glucose uptake begins to develop. In 7-day-old and older hearts, glucose transport becomes the rate-limiting factor of glucose uptake. 3) These and other properties of the chick embryo heart make it a convenient tool for the study of permeability and transport phenomena.
Direct measurements of the early erythropoietic effect of anemia
Authors: Erslev Allan J. , Boissevain Andre R.
Published: December 2017

Measurements were made in normal rabbits of the early effect of acute anemic anoxia on the level of erythropoietic factor and on erythropoietic tissue. The erythropoietic factor was found to be increased 3 hr after the onset of anemic anoxia and before measurable changes could be detected in the erythropoietic tissue. The subsequent production and release appeared to be directly proportional to time. Bone marrow changes during the 8-hr experimental period were more difficult to measure. The best technique appeared to be a simple differential count with the measurement of the ratio between early and late nucleated red blood cells. In vitro bone marrow incorporation of Fe59 could be used only if the bone marrow volumes studied were of identical size, a requirement difficult to fulfill. Plasma iron turnover was not sensitive enough to measure early bone marrow changes.
Electrical conductivity and electrolyte distribution in a secreting salivary gland
Authors: Harreveld A. Van , Potter R. L. , Sloss L. J.
Published: December 2017

During the first 4–7 min of pilocarpine-induced secretion the submaxillary gland lost a large part of its electrical conductivity (a mean loss of 40% in 8 experiments). In preparations of control and experimental glands treated with a histochemical method for chloride a marked loss of fluid and electrolytes from the intertubular spaces could be demonstrated during this period. This loss of extracellular electrolytes provides an explanation for the drop in conductivity of the gland. A comparison of control and experimental glands showed that during the first minutes of secretion the gland lost water and total solids, decreased in potassium and chloride content, gained sodium, and increased slightly in total cation concentration.
Residual radiation injury: impaired regrowth of realimented hypocalorically reared rats
Authors: Carroll H. W. , Brauer R. W.
Published: December 2017

Hypocalorically reared rats were subjected to single exposures of X ray ranging from 400–700 rad or to repetitive exposures of 200 rad in four doses spaced 1 week apart (total 800 rad). They were allowed to recover for a minimum of 7 weeks and a maximum of 6 months after the last exposure and then returned to an adequate caloric intake. Realimentation of the irradiated populations resulted in reduced regrowth when compared to nonirradiated realimented rats of the same age. The reduction in regrowth persisted regardless of radiation exposure patterns, realimentation patterns, or the recovery periods here employed. Paired feeding demonstrated that the regrowth reduction is primarily one of reduced nutrient utilization. Gastrointestinal tract shielding showed that injury to the intestinal region with impaired absorption is probably not the cause. It is concluded that the reduced regrowth of the irradiated realimented rats is a generalized deficiency of nutrient utilization by the organs and tissues, perhaps mediated through the endocrines.
Acceleration of thrombin activity with Ac-globulin
Authors: Seegers Walter H. , Landaburu Ricardo H.
Published: December 2017

Purified Ac-globulin preparations accelerate the hydrolysis of p-toluenesulfonyl-l-arginine methyl ester (TAMe) by thrombin. Ac-globulin is the limiting factor in the reaction and does not itself hydrolyze TAMe. The increased thrombin activity is directly proportional to Ac-globulin concentration. More than a 25-fold increase in thrombin activity was obtained. The basic principle of accelerating TAMe hydrolysis with thrombin is tentatively proposed as a quantitative assay for Ac-globulin. A function of Ac-globulin in prothrombin activation is to increase the effectiveness of thrombin in the proteolytic degradation of the prothrombin substrate.
Thoracic duct lymph of mice after saline treatment of tourniquet shock
Authors: Shrewsbury Marvin M.
Published: December 2017

Tourniquet shock was produced in mice with thoracic duct fistulas, untreated or treated with saline. Lymph volume and sodium and potassium output were determined. Tourniquet shock in untreated fistula animals caused a decrease in lymph flow and sodium output, compared with untreated controls. Potassium output was not increased in shocked untreated animals when compared with output in untreated controls. Lymph flow and sodium output in lymph were significantly less for saline-treated shocked animals than for saline-treated controls; potassium output in the lymph of saline-treated shocked animals was elevated to the same level as for saline-treated controls. Previous workers have demonstrated an increase in potassium content of nontraumatized tissues and of blood after tourniquet shock. Moreover, in the present experiment potassium concentration increased in lymph of untreated shocked mice. The output of potassium, however, in the lymph of untreated shocked animals did not reflect this increase except when the flow of lymph was augmented after saline administration.
Anti-inflammatory properties of lyophilized inflammatory exudates
Authors: DiPasquale G. , Girerd R. J.
Published: December 2017

Lyophilized granuloma pouch exudates obtained from intact or adrenalectomized rats contain an anti-inflammatory substance active parenterally in the cotton pellet and in the granuloma pouch methods. In these crude preparations the activity is only a small fraction of that of cortisone acetate. Both exudates are active in hypophysectomized animals but not in adrenalectomized animals. It appears that the active fraction is not itself an adrenal steroid, but it is possible that small amounts of adrenal hormones act as conditioning factors for the anti-inflammatory activity. The release of a nonadrenal anti-inflammatory substance during inflammation would help explain some anergic phenomena; such a substance could also be involved in limiting and terminating the inflammatory process.
Unipolar and bipolar electrodes in self-stimulation experiments
Authors: Valenstein Elliot S. , Beer Bernard
Published: December 2017

Experiments were conducted in which response rates for different intensities of reinforcing intracranial stimulation were obtained with both bipolar and unipolar electrodes. Subsequent experiments were designed to clarify differences resulting from these two types of stimulation. Experimental subjects were albino rats and rhesus monkeys. Using biphasic stimulation it was found that self-stimulation rates were consistently lower with unipolar electrodes than with bipolar ones. These lowered response rates appeared to result from the alternation of the cathode and anode between the deep electrode and the indifferent surface electrode. Subsequent experiments with monophasic current demonstrated the significance of the location of the cathode and anode for self-stimulation experiments. The results of an attempt to evaluate the relative area of effective current spread with unipolar and bipolar electrodes are also reported. It was found that in anesthetized monkeys with unipolar electrodes, rhythmic vocalization could be elicited more often, and over a significantly greater area surrounding the periaqueductal gray than when bipolar electrodes were used.