bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Thyroid Function on the Metabolism of the Anterior Pituitary Gland
Authors: Levey Harold A. , Roberts Sidney
Published: December 2017

The weight and rate of oxygen consumption of the anterior pituitary gland of the male Sprague-Dawley rat were observed to decline with age. Thyroidectomy, administration of thiouracil or propylthiouracil, and castration significantly elevated pituitary weight, while all but the latter procedure resulted in increased oxygen consumption of this gland. Adrenalectomy was without effect in these respects. Pituitary hypertrophy after thyroidectomy was associated with hyperemia and increased water and protein content. No changes were observed in glucose utilization, lactate production, and levels of succinic dehydrogenase and cytochrome oxidase in the pituitary gland following thyroidectomy. Administration of thyroxine to thyroidectomized rats restored normal pituitary weight and respiratory activity. Diiodothyronine and triiodothyronine were somewhat less effective than thyroxine. Diiodotyrosine and potassium iodide were ineffective. The relationship of pituitary metabolism to protein hormone synthesis in this gland is discussed.
Placental Transfer of Calcium and Strontium in the Rat and Rabbit
Authors: Wasserman R. H. , Comar C. L. , Nold M. M. , Lengemann F. W.
Published: December 2017

The comparative metabolism of calcium and strontium during fetal development was investigated in rats and rabbits using double tracer techniques. In general, the placental transfer from dam to fetus of strontium was about one-half that of calcium; the site of discrimination was the placental barrier. The major discrimination occurred in movement of Ca* and Sr* from dam to fetus, with little or no differential movement from fetus to dam. Under steady state conditions in the rat the relative Sr*/Ca* ratios in the fetus, maternal skeleton and diet were 0.17, 0.28 and 1, respectively. The over-all discrimination of 0.17 between fetus and diet resulted from absorption (0.42), urinary excretion (0.63) and placental transfer (0.65). In the rat it was estimated that 92% of the fetal calcium had originated from the maternal diet. In the rabbit during late pregnancy, it was determined that about 24 mg of calcium/fetus/day moved across the placenta as compared with a need of about 13 mg for fetal development.
Changes in Cell and Plasma Volumes in the Dog Produced by Hemorrhage and Reinfusion
Authors: Huggins R. A. , Smith E. L. , Deavers S. , Overton R. C.
Published: December 2017

Sixteen dogs were anesthetized with a combination of morphine and pentobarbital. They were bled slowly into a bottle until the mean blood pressure was 35.0 ± 2.0 mm Hg. Blood volume was determined by red cells tagged with radioactive Cr51 and injected at various times during the experiments. All figures are averages of the 16 dogs. At the end of the bleeding period 9.5 cc/kg of plasma was mobilized but 3.0 cc/kg of the original volume of red cells was trapped. On reinfusion the 9.5 cc/kg of plasma that had been mobilized and 8.2 cc/kg of the dog's original plasma were removed from the circulation or trapped. No more red cells were trapped, but those previously trapped were not released. The final blood volume after reinfusion (69.3 cc/kg) was therefore less than the control blood volume (81.4 cc/kg). Because of the ability of the circulation to adjust the circulating volume by trapping red cells and adding or removing plasma, it is essential to use additional injections of the material to be measured if a change in blood volume is suspected.
Effects of Anoxia on Pulmonary Circulation: Reflex Pulmonary Vasoconstriction
Authors: Aviado Domingo M. , Ling Johnson S. , Schmidt Carl F.
Published: December 2017

The inhalation of 5 or 10% oxygen in anesthetized dogs causes increased pulmonary arterial pressure, increased pulmonary blood flow (measured directly by cannulalation of one lobar vein) but increased or decreased pulmonary vascular resistance. At least four opposing factors are responsible for the variable effects of anoxia on vascular resistance, namely: a) reflex pulmonary vasoconstriction from anoxic stimulation of chemoreceptors in the carotid and aortic bodies (demonstrable in innervated lobe that is perfused and ventilated independently of all other lobes); b) local pulmonary vasodilatation (brought about by reduction in oxygen content of the air ventilating or of the blood perfusing the lobe); c) passive reduction in pulmonary vascular resistance secondary to anoxic increase of pulmonary blood flow; and d) liberation of epinephrine capable of stimulating the heart and constricting the lung vessels. The reflex pulmonary vasoconstriction can be demonstrated only if the perivascular nerve fibers are preserved. This reflex response is mediated by the thoracic sympathetics and is activated by less severe anoxemia (reduction of arterial oxygen saturation by at least 10%) as compared to the other mechanisms (local and passive dilatation which require reduction of saturation by at least 30%).
Relationship Between Development of Fractures During ECS, Type of Convulsion and Weight of Animals
Authors: Stern John A. , McDonald David G. , Werboff Jack
Published: December 2017

Two distinct types of seizure patterns, a tonic-clonic and a clonic convulsive pattern were observed in male albino rats undergoing a series of electroconvulsive shocks. A significant relationship between weight and type of convulsive pattern was found. Only animals which developed ‘clonic-only’ seizure patterns developed hind leg paralysis.
Trigemino-Bulbar Reflex Pathways
Authors: Green John D. , De Groot Jacob , Sutin Jerome
Published: December 2017

In decerebrate and decerebellate cats stimulation of any division of the trigeminal nerve induces efferent volleys in the VIIth, Xth, XIth and XIIth nerves. Direct stimulation of the face, internal nares and dura mater produces similar volleys. In uncurarized animals similar stimuli cause twitches of face and neck muscles. Slowing of the heart rate may also be induced. Conduction times measured in the brainstem and cranial nerves show that conduction is very rapid in the brainstem to the level of the obex, so that large medullated fibers may be inferred. At the level of the obex a delay of 2–4 msec. occurs, presumably due to synapses and internuncial neurones. Conduction of the volleys in the Xth and XIth nerves is rapid and large fibers must be involved. Removal of the dorsal vagal nuclei does not abolish the vagal reflex which is presumed to relay at the nucleus ambiguus. The vagal responses are very easily fatigued.
Acetylcholine Concentrations in the Brain of Rabbits Exhibiting Forced Turning Movements
Authors: Aprison M. H. , Nathan P.
Published: December 2017

Values for the free ACh concentration in the left and right cerebral cortex and caudate nuclei are given for normal rabbits as well as for animals exhibiting compulsive circling movements as a result of an unilateral (right) intracarotid injection of DFP. In animals exhibiting forced circus movements in either direction a marked asymmetry in ACh content existed between the left and right cerebral cortex as well as the left and right caudate nucleus. In rabbits circling to the left, the ACh content was higher on the right side in both the cortex and caudate nucleus. However, in rabbits turning compulsively to their right, the left cortex had a higher ACh concentration than the opposite side. In the case of the caudate nuclei, the right side was higher than the left. Since previous ChE data as well as the present ACh data for the caudate nuclei in ‘righters’ and ‘lefters’ show little difference it is difficult to implicate the caudate alone in the mechanism of compulsive turning. It is thought that the caudate nucleus may be involved in a secondary manner in the production of rabbits circling to the left. However, the biochemical evidence does suggest that stimulation due to the accumulated ACh on one side of the cerebral cortex may be the primary factor in causing the animal to exhibit compulsive circling toward the contralateral side.
Role of Pituitary, Adrenal and Kidney in Several Thyroid Responses of Cold-Exposed Hamsters
Authors: Knigge Karl M. , Goodman Robert S. , Solomon David H.
Published: December 2017

The role of the pituitary, adrenal and kidney was investigated in several of the thyroid responses to acute and chronic cold exposure. The pituitary gland is necessary for: a) maintenance of normal thyroid weight, histology and I131 uptake in hamsters housed at room temperature; b) survival of cold-exposed hamsters; and c) the increased thyroid I131 uptake occurring during cold exposure. The initial effects of cold exposure evoke a brief period of accelerated release of thyroidal I131 followed by complete inhibition of release Also during the period of initial cold exposure, I131 uptake is sharply depressed, probably because of an increase in renal elimination of iodide. This renal mechanism is independent of the adrenal glands but appears to require the presence of the pituitary.
Myotrophic Effects of Castration and Testosterone in Thyroidectomized Guinea Pigs
Authors: Kochakian Charles D. , Tillotson Carol
Published: December 2017

Male guinea pigs of the inbred Hartley strain were castrated, thyroidectomized and castrated-thyroidectomized at 470–549 gm body weight. Thyroidectomy did not change the rate of growth of the body, carcass, internal organs or 48 individual muscles during the ensuing 51 days in either the normal or castrated animals. The administration of testosterone during the last 21 days in a group of castrated-thyroidectomized animals partially restored the weight of the castration-atrophied muscles while the seminal vesicles and prostates were increased to slightly above normal.
Effect of Inositol and Rapid Rewarming on Extent of Tissue Damage Due to Cold Injury
Authors: Sullivan Bernard J. , LeBlanc M. Francis
Published: December 2017

There is an inverse relationship between the extent of edema and the degree of tissue loss due to cold injury. Rapid rewarming favors edema but reduces tissue necrosis. Inositol markedly increases edema in nonrewarmed controls but considerably reduces tissue loss. Maximum therapeutic results were obtained through the simultaneous use of rapid rewarming and inositol injection, although rewarming proved to be the best single therapy. The tissue damage due to cold injury is directly proportional to the duration of exposure to cold.
Conditioning of Rats to Tumbling Trauma by Electroconvulsive Shock
Authors: Griswold Robert L. , Gray Irving
Published: December 2017

Rats were made relatively resistant to the lethal effects of tumbling trauma by a previous series of electroconvulsive shocks (ECS). ECS causes an immediate marked rise in the plasma concentrations of adrenaline and noradrenaline, as a result of the electrical stimulation of the sympathetic nervous system. The plasma concentrations of adrenaline and noradrenaline, which are elevated in response to trauma, show a more rapid fall after termination of trauma in the ECS-conditioned animals than in controls. There is no significant alteration in the sensitivity of ECS-conditioned rats to toxic doses of adrenaline and noradrenaline. It is thought that ECS-conditioning, and probably also the conventional drum-conditioning, are brought about by a diminished reactivity of the sympathetic nervous system after its repeated stimulation.
Effect of Egyptian Black Snake Toxin on Histamine of Blood and Its Relation to Blood Eosinophils
Authors: Mohamed A. H. , Zaki O.
Published: December 2017

The Egyptian black snake Walterinnesia is an extremely poisonous snake which lives in the Sinai desert near Suez. Many fatal attacks of this snake to camping soldiers and local inhabitants have been reported. This works shows that the injection of sublethal and lethal doses of the purified toxin causes an increase in the blood histamine. The effect on the circulating eosinophils varies, while the sublethal dose of the toxin causes reduction in their number, the lethal dose causes a significant increase. The eosinophil leucocyte is not of special importance as a carrier of blood histamine. The change in blood histamine is probably a quite separate mechanism which has no relation to suprarenal cortex activity or to the change in the number of blood eosinophils.
Renal Functions in the Chimpanzee
Authors: Gagnon John A. , Clarke Robert W.
Published: December 2017

The excretion of creatinine and para-aminohippurate in five chimpanzees was found to be both by glomerular filtration and tubular secretion with mutual interference between the secretory processes. No evidence was found to suggest that inulin is subject to tubular secretion or reabsorption and it is therefore still acceptable for the measurement of glomerular filtration. The absolute values of glomerular filtration and renal excretion of creatinine and para-aminohippurate may have been modified by the use of anesthesia, but no striking differences are apparent between the kidney of the chimpanzee and that of man. PAH at high plasma concentration increases the excretion of potassium.
Radiophosphorus Measurement of the Lifespan of Lymphocytes in the Rabbit
Authors: Coassin Nicholas A. , Kline Daniel L.
Published: December 2017

Measurements of the lifespan of lymphocytes from radioisotope data yield a value of about 2 weeks whereas thoracic duct collection indicates that the circulating lymphocytes are replaced twice daily. In an attempt to reconcile these findings, the relationship of lymphocytes in nodes, thoracic duct and peripheral blood was studied by means of radio phosphorus labeling. A correlation was found between the specific activity of the deoxyribose-nucleic acids (DNA) of lymphocytes in the nodes and duct. A rougher correlation was observed between the node and blood lymphocytes. Both node and blood DNA specific activity showed diphasic curves of 3- and 12-day duration. With operative trauma, labeled cells disappeared from the nodes and blood. Nonlabeled cells, probably extravascular, entered the circulation. The conclusion is reached that lymphocytes persist in the blood stream for a minimum of 12 hours as shown by the collection data, for 15 days in the nodes and blood stream as demonstrated by the isotope findings and that, in addition, these cells persist in extravascular locations for a length of time not measured by either of these techniques.
Biphasic Hyperferremia Induced in Rats by X-Irradiation
Authors: Melville G. S. , Conte F. P. , Upton A. C.
Published: December 2017

The hyperferremia that developed in rats after a single dose of 75–225 r of total-body X-irradiation occurred in two distinct phases. A transient rise in plasma iron occurred within the first 24 hours after irradiation, and a more prolonged elevation took place during the 2nd week after exposure. The concentration of plasma iron in normal rats varied from day to day and in relation to the hour of sampling.
Aorta and Smooth Muscle Electrolytes During Early and Late Hypertension
Authors: Daniel Edwin E. , Dawkins Oswald
Published: December 2017

Tissue electrolytes in the early phase of hypertension initiated by DCA have been compared with those in later persistent hypertension. In smooth muscle (aorta and stomach muscle) significant potassium depletion occurs during early hypertension in comparison with tissues from treated normotensive animals. A tendency for increased sodium concentration also developed. However, no significant changes from normotensive controls could be demonstrated in aorta during post-DCA, renal or spontaneous hypertension of long duration. These results suggest that there are differences in the disturbances in vascular smooth muscle electrolytes accompanying early and late hypertension. Differences in age or composition of the control groups and in the degree of hypertension produced may explain differences between these results and those of previous workers. None of the other tissues analyzed (left ventricle and psoas muscle) showed changes in electrolyte distribution characteristic of chronic hypertension.
Oxygen Consumption of Liver Following Subtotal Hepatectomy of Normal and Hypothyroid Rats
Authors: Schwartz Herbert S. , Barker S. B.
Published: December 2017

Respiration of regenerating liver was compared with the rate of regeneration at varying intervals after removal of the left lateral and median lobes of the liver of rats. This subtotal hepatectomy was found to remove 66% of the total liver of rats in a comparable weight range; control animals were laparotomized, the liver was exposed for the same length of time, and the viscera were manipulated in an analogous manner. At 1, 2, 3, 4, 7 and 14 days postoperative, the rats were killed by exsanguination, the liver remnant was weighed and slices prepared for manometric studies in Ringer-phosphate-glucose medium. At 3 days, when growth was most rapid, liver respiration was increased 40%. By 14 days, when the liver had reached its calculated preoperative weight and growth had slowed considerably, respiration was 14% higher than controls. Hypothyroid rats, prepared by previous thyroidectomy, had a lower rate of liver regeneration after hepatectomy, but respiration, although at a lower level, showed comparable stimulation.
Effect of Fasting on Liver Enzymes Involved in Glucose-6-Phosphate Utilization
Authors: Weber George , Cantero Antonio
Published: December 2017

Effect of 24-hour fasting on liver enzymes involved in G-6-P utilization (phosphoglucomutase, phosphohexoseisomerase and G-6-P dehydrogenase) was studied. The 24-hour fasting caused a decrease in liver mass and an increase in cellularity. Total cellularity, however, did not change. Nitrogen content of the liver homogenate and supernatant fluid was apparently unaltered after 24-hour fasting when values were expressed on a wet weight basis. Nitrogen content significantly decreased in the average cell, in the whole liver and per 100 gm body weight. Changes in liver enzymatic activities were also masked by the shrinkage of the liver. The activities of the three enzymes examined showed only apparent alterations when expressed per wet weight or per nitrogen basis. However, when enzymatic activities were expressed per average cell, phosphoglucomutase and phosphohexoseisomerase showed a statistically significant decrease after 24-hour fasting. The total liver and total available phosphoglucomutase and phosphohexoseisomerase activity also decreased significantly.
Stress and the Thymus
Authors: Kramár Jenö , Simay-Kramár Margaret
Published: December 2017

Role of the thymus in the alarm reaction was investigated on albino rats by studying the capillary resistance and the capillary stress response after thymectomy. Control animals were of the same breed, weight and sex and they matched the thymectomized rats also in that they were exposed to the same surgical trauma (sham thymectomy). No difference was found between thymectomized and control animals as far as general development, weight, maturation, life span, resistance to infections or capacity to endure stressful situations were concerned. The capillary resistance level did not change in these two groups of rats during an observation period of 3–10 months. Typical capillary response was found to most varied forms of stress in the thymectomized as well as in the sham operated animals. Adrenalectomy in the thymectomized rats resulted in capillary resistance changes similar to those in the sham operated or intact controls. Adrenalectomy abolished the late response but did not interfere with the immediate response in the presence as well as in the absence of the thymus. The conclusion is warranted that the thymus does not influence capillary resistance or the capillary stress response. No proof was forthcoming in these experiments in favor of a specific role of the thymus in the alarm reaction.
Freezing and Freeze-Drying of Bull Spermatozoa
Authors: Sherman J. K.
Published: December 2017

The possible dependance of survival upon the time spermatozoa are in contact with the protective substance glycerol, prior to exposure to low temperatures, was investigated. Pretreatment for 5 minutes provided at least as much protection as 18 hours. Microscopic observations on ice formation relative to survival in semen frozen by four different methods, in the presence and absence of glycerol, gave no evidence for the notion that physical injury by ice is the cause of death on freezing and thawing. Site and character of ice formed were preserved by freeze-drying. A study on the effect of rates of cooling on survival revealed that the theory of survival based upon vitrification by rapid cooling does not apply to bull spermatozoa. Spermatozoa in smears of semen on glass slides did not withstand the process of freeze-drying for various periods. Death was attributed to drying and/or reconstitution.
Plasma Concentration of Epinephrine and Norepinephrine in Hemorrhagic and Anaphylactic Shock
Authors: Manger William M. , Bollman Jesse L. , Maher Frank T. , Berkson Joseph
Published: December 2017

A fluorometric method was used to quantitate plasma epinephrine and norepinephrine during hemorrhagic and anaphylactic shock in healthy adult dogs anesthetized with pentobarbital. Arterial plasma was analyzed before and after hemorrhage in four dogs. Loss of approximately 18% of blood volume through rapid arterial bleeding caused no remarkable change in pressor amines. Loss of approximately one-third of the total blood volume decreased the mean arterial pressure by a range of 56–81% and invariably caused increased concentration of plasma pressor amines. The average concentration of epinephrine increased from 1.0 to 7.8 µg/1. of plasma, and that of norepinephrine increased from 2.5 to 3.6 µg. Additional bleeding caused further increase of plasma pressor amines. Seven dogs were given egg white intravenously to sensitize them. Subsequently, whenever a severe reaction (hypotension, bradycardia and respiratory depression) resulted from intravenous administration of egg white, venous plasma pressor amines increased. The average concentration of epinephrine increased from 0.7 to 7.7 µg/1. of plasma; norepinephrine increased in three dogs but remained unchanged or decreased in the remaining animals. Without a preceding ‘shock’ reaction, change in concentration of epinephrine-like substance was unremarkable. Intravenous administration of 1 mg of histamine base produced hypotension and usually slight increase of plasma pressor amines.
Circulation and Blood Pressure in the Great Vessels and Heart of the Turtle (Chelydra serpentina)
Authors: Steggerda F. R. , Essex Hiram E.
Published: December 2017

Circulation through the heart of the turtle ( Chelydra serpentina) was studied by means of simultaneous recordings of oxygen saturation, blood-saturation dye curves and pressure measurements in the cardiac chambers and arteries leaving the heart. The saturation levels of the blood leaving the heart via the right and left aortas are the same while pulmonary artery blood is distinctly more venous. Resection of the septal mechanism resulted in oxygen saturations of similar value in all vessels leaving the heart. The dye curves showed that less than 10% of the blood of the turtle may pass from right to left but a much larger volume of blood passes from left to right. The findings in the turtle heart resemble those found in human patients with congenital ventricular septal defects. Blood pressure patterns in the carotid, subclavian arteries and the two aortas are very similar. Systolic pressures in the aortas and pulmonary artery are the same, but diastolic pressure in the pulmonary artery is distinctly lower than in the aortas.
Failure of the Bulbar Inhibitory Reticular Formation to Affect Somatic Reflex Activity in the Unanesthetized Cat
Authors: Mandell A. J. , Bach L. M. N.
Published: December 2017

Bulbar inhibition of the patellar reflex was obtained under Nembutal anesthesia in cats at surgery when stimulating electrodes were implanted aseptically in the medullary reticular formation. After periods of 72–322 hours of postoperative recovery it was impossible to obtain inhibition of the patellar reflex even at stimulus voltages which produced convulsive activity. Reinduction of Nembutal anesthesia prior to killing always resulted in the reappearance of bulbar inhibition. Autonomic, respiratory and EEG desynchronization effects were always obtainable whether or not the animal was anesthetized. Etherized animals exhibited the usual bulbar inhibition of the patellar reflex, lost the inhibition when when removed from ether and regained the inhibition when re-anesthetized with ether. The authors conclude that either chemical (anesthetic) or surgical (decerebrate) removal of suprabulbar structures is required for the demonstration of bulbar reticular inhibition of the patellar reflex by direct stimulation of the reticular formation.
Influence of Purified Adrenal Hormones and Adrenocorticotropin on Progesterone in Decidual Tissue Formation
Authors: Velardo Joseph T.
Published: December 2017

The ovariectomized, pseudopregnant mouse was used to test the effect of cortisone (compound E), hydrocortisone (compound F), 11-desoxycorticosterone and ACTH on the action of progesterone in decidual development. It was observed that following ovariectomy and unilateral uterine traumatization on the 5th day of pseudopregnancy, 0.25 mg progesterone daily on this day of pseudopregnancy and for 3 subsequent days effected a 289% increase over the nontraumatized, contralateral cornu; 0.5 mg daily a 338% increase; 0.75 mg a 440% increase; 1.0 mg a 528% increase, and 1.5 mg a peak reaction of a 615% increase. Larger dosages of progesterone did not produce decidual reactions that were significantly greater than the 615% figure. For the studies involving progesterone and the other compounds named above, 0.75 mg of progesterone was used as the standard daily dose. These results indicate that a 1:1 ratio of ACTH to progesterone inhibits the response of the traumatized uterus from the control figure of 440% down to 100%. Compounds E and F were both quite effective in restricting the action of progesterone, a 1:1 and 2:1 ratio being required of compounds E and F, respectively, for the level of inhibition obtained with ACTH. Tested alone, none of the three compounds (E, F and ACTH) displayed the ability to induce decidual reactions. Desoxycorticosterone, which is progestational, did not inhibit or augment the response to progesterone. These data give added credence to the thought that there may be numerous actions and interactions on the ovarian-uterine-adrenal level.
Production of Xanthurenic Acid From Tryptophan in Pregnancy and in Various States of Nitrogen Balance
Authors: Hawkins W. W. , Leonard Verna G. , Coles Carol Marie
Published: December 2017

Production of xanthurenic acid from tryptophan was studied in pregnant women, in pregnant rats and in rats in vitamin B6 deficiency and various states of nitrogen balance. Of eight women well advanced in pregnancy only one excreted excessive xanthurenic acid after a test dose of tryptophan, and this pregnancy was complicated by disease. The excessive excretion in this case was reduced by dosage with pyridoxin. Rats late in pregnancy and early in the post-partum period typically excreted abnormally large amounts of xanthurenic acid after test doses of tryptophan. The administration of extra vitamin B6 or of other B vitamins had no effect. After the same level of dosage with tryptophan the excretion of xanthurenic acid by rats well advanced in vitamin B6 deficiency was much higher than that by pregnant rats. No conclusive evidence was obtained that the production of xanthurenic acid from tryptophan is associated with the state of nitrogen balance as influenced by pregnancy, vitamin B6 deficiency, or the intake of protein. Some of the experimental results suggested, however, that outside of vitamin B6 deficiency it tends to be high when the retention of nitrogen is high.
Respiratory Metabolism During Pregnancy in the Guinea Pig
Authors: Hoar Richard M. , Young William C.
Published: December 2017

Oxygen consumption and heart rate during pregnancy were measured in untreated, thyroxin-injected and thyroidectomized guinea pigs given I131. From impregnation until parturition, oxygen consumption increased 7.9% in untreated females. The increase continued until 5 days postpartum when a sharp decrease occurred. The increase is not accounted for by growth of the fetal mass. Comparable increases occurred in thyroxin-injected (16.2%) and thyroidectomized (11.9%) females, although the levels throughout were higher and lower, respectively, than in intact females. Heart rate did not increase. On the contrary, statistically significant decreases occurred in the untreated and thyroxin-injected females. Although the mechanism associated with the increased metabolic rate is not known, the possibility of thyroid participation would seem to be excluded. Involvement of the adrenal cortex is suggested by morphological differences in the cells of the zona fasciculata in pregnant and nonpregnant females and by evidence cited from other studies.
Mechanism Underlying Hypercholesteremia Induced by Triton WR-1339
Authors: Friedman Meyer , Byers Sanford O.
Published: December 2017

Sequential changes in the plasma lipids of rats injected with Triton were studied. It was observed that following a dose of Triton, the accumulation of triglyceride (neutral fat), cholesterol and phospholipid proceeded in plasma for about 36 hours, after which time a rapid diminution began. Excess triglyceride began both to accumulate and to disappear, respectively, before the other two substances. During the phase of accumulation, the excess cholesterol in plasma was not found to be reflected by any increase in cholesterol either in the liver tissue or in hepatic lymph. This lack of diffusibility of plasma cholesterol disappeared during the period of recovery. Injection of Triton retarded the escape of both injected triglyceride and phosphatide from the plasma of the liverless rat. Hypercholesteremia could be induced in the liverless rat by Triton injection if triglyceride, phosphatide or both were given with the Triton. It is suggested that the hypercholesteremia occurring after injection of Triton is due to the latter's ability to retain excess triglyceride and phospholipid which then in turn mobilizes and sequesters cholesterol from both extrahepatic and hepatic sources.
Effects of Choline Deficiency and Carnitine on Palmitic Acid Oxidation by Rat Liver Homogenates
Authors: Fritz Irving B.
Published: December 2017

The conversion of C14 carboxyl-labeled palmitic acid to CO2 and ketones by liver homogenates prepared from choline deficient rats maintained on a 20% protein diet was within the normal range, indicating that hepatic fat oxidation is not impaired in the absence of choline alone. Carnitine addition in vitro augmented ketogenesis by livers from all groups of rats tested, while choline addition in vitro was without effect. Choline administration in vivo resulted in an enhanced oxidation of palmitic acid to CO2 by liver homogenates obtained from choline-deficient animals. However, liver preparations from animals injected in vivo with choline continued to respond to carnitine addition in vitro with an enhanced ketogenesis. It was concluded that carnitine and choline influence different parameters of fat metabolism.
Influence of Temperature on Performance in Guinea Pigs
Authors: Wilber Charles G.
Published: December 2017

Guinea pigs were forced to swim to total exhaustion in water at various temperatures. Small animals (400 gm) showed peak performance at about 40°C, large ones (1000 gm) at about 35°C. Large animals swam longer at low temperatures but shorter at high temperatures than did small ones. At 35°C all guinea pigs swam for an average of about 150 minutes. In general this species shows much less capacity for swimming than do albino rats. The difference may be related to diet or to endocrine factors.
Experimental Mitral Stenosis and Ascites Formation
Authors: Hamilton William F. , Davis James O. , Howell David S. , Ellison Robert G. , Hague Elmer E. , Brown Walter J.
Published: December 2017

Extreme care must be taken in the production of experimental mitral stenosis in dogs by the method of controlled progressive constriction of the mitral ring in order to prevent the inadvertent constriction of the thoracic inferior vena cava and resultant elevation of the inferior caval pressure. After a report from Hamilton, Ellison, Hague and Brown (Georgia Laboratories) that ascites formation was a common occurrence in dogs with experimental mitral stenosis produced by this technique, an attempt was made by Davis and Howell (Bethesda workers) to repeat these observations. From experiments performed in Bethesda, it was found that a stricture of the thoracic inferior vena cava was produced when the Georgia technique for production of mitral stenosis was used; this constriction provided an explanation for the ascites formation. These results were communicated to the Georgia workers who explored the two surviving dogs of their first series and found evidence which suggested that the inferior vena cava was patent even though the dogs were producing ascites profusely. Later, the Georgia group produced mitral stenosis in two additional dogs by the original technique and these animals gave unequivocal evidence that the stricture was present. Great care was then taken by the Georgia workers in placing the constricting ligature to avoid stricture of the orifice of the inferior vena cava. Of the 13 dogs so treated only 1 produced ascites and it had a small obstruction in the inferior vena cava. These last experiments by the Georgia workers as well as those of the Bethesda group suggest that ascites does not occur secondary to experimental mitral stenosis in dogs.
Saline Therapy in Tourniquet Shock
Authors: Andree Ronald A. , Wingard Daniel W. , Koletsky Simon
Published: December 2017

Tourniquet shock in rats was treated by saline infusions ranging in amount from 6 to 25% of body weight. The 6% infusions gave temporary improvement and prolonged life but did not prevent death. With 12% infusions about half the animals survived the acute stage of shock. When the quantity of saline was equal to 18% of body weight the results were excellent and 84% of animals survived the shock state. Survival was not improved when the infusion amounted to 25% of body weight. The success of saline therapy in tourniquet shock was clearly dependent on the volume of fluid employed. A huge quantity of saline was required to obtain saturation of the tremendous edema potential in the injured leg and also to provide a surplus for retention in the circulation with relief of hypovolemia and hemoconcentration.
Serum Transaminase Changes After Local Injury
Authors: Albaum Harry G. , Milch Lawrence J.
Published: December 2017

Small, but statistically significant, increases of serum glutamic oxalacetic transaminase (G-O-T) are shown to be associated with local irradiation injury in the rabbit. Similar results are observed after crush injury. If the rabbit leg is subjected to 3 hours of tourniquet ischemia, however, G-O-T elevations of extent comparable to human myocardial infarction and acute hepatocellular damage are observed.
Changes in Cortical pH and Blood Flow Accompanying Spreading Cortical Depression and Convulsion
Authors: Tschirgi Robert D. , Inanaga Kazutoyo , Taylor J. Langdon , Walker Robert M. , Sonnenschein Ralph R.
Published: December 2017

Local changes in cerebral cortex hydrogen ion concentration of as much as 0.5 ph units were observed to accompany the waves of cortical spreading depression or convulsion in cats and rabbits. A diphasic wave consisting of an initial alkaline followed by a more prolonged acid shift was observed in most cases. No significant differences were found between the ph changes accompanying spreading depression and those accompanying spreading convulsion. These ph shifts, like the abnormal ECG activity and the slowly changing potential wave which accompanied them, spread over the surface of the cerebral cortex with a velocity of 1–3 mm/min. The curve of cortical ph change is coincident with, and similar in shape to, the slowly changing potential difference measured between a point on the cortical surface and the jugular blood. For every unit change in ph, the cortex-blood P.D. is shifted approximately 30 mv. It is suggested that the slowly changing potential difference arises across the blood-brain barrier rather than as a result of depolarization of neuronal membranes. A significant but variable change in local blood flow accompanied the spreading depression.
Renal Excretion of Phlorizin and Phlorizin Glucuronide
Authors: Braun Walter , Whittaker Victor P. , Lotspeich William D.
Published: December 2017

A study was made of the excretion of the glycoside, phlorizin, in the dog using the phenol method of Folin and Ciocaltieu combined with separation of phlorizin from other phenols by filter paper chromatography. Phlorizin was found to be filtered through the glomeruli and secreted by the tubules. The phenomenon of tubular secretion of phlorizin was also observed in the domestic chicken and the aglomerular fish, Lophius americanus. In the dog the tubular secretion of phlorizin is inhibited by Benemid and p-aminohippurate. The glucuronide of phlorizin was found in plasma and urine of the dog and urine of the chicken during phlorizin infusion. It is excreted predominantly by glomerular filtration in the dog during phlorizin administration. Benemid, while blocking tubular secretion of phlorizin, uncovers a tubular secretion of the glucuronide. The interrelations between phlorizin and phlorizin glucuronide in tubular secretion are discussed as well as the relation of the transport of these same two substances to the phlorizin block of secretion of phenol red, Diodrast and p-aminohippurate and the reabsorptive inhibition of glucose.
Responses Evoked at the Cortex by Tooth Stimulation
Authors: Melzack Ronald , Haugen Frederick P.
Published: December 2017

Evoked potentials have been recorded at the cortex of the curarized cat following stimulation of the tooth pulp. The majority of the afferent potentials have been classified into two main categories: A) short-latency potentials from the contralateral tooth only, which were unaffected by the administration of a mixture of nitrous oxide and oxygen. These responses were observed in the ventral portion of the coronal gyrus. B) Potentials with longer latencies than those of A, which were evoked by stimulation of both the ipsilateral and contralateral teeth and which were markedly diminished in amplitude by the nitrous oxide mixture. The main source of these potentials was an area rostral to, and overlapping with, the area at which the short-latency contralateral potentials were recorded. They were also observed in the ventral portion of the anterior ectosylvian gyrus. The functional characteristics of the potentials in categories A and B are such as to suggest that these potentials represent tooth pulp projections to the cortex by way of the trigeminal lemniscus and the trigemino-bulbo-thalamic tracts, respectively.
Vascular-Extravascular Equilibration of Radioactive Iodinated Albumin in Mice
Authors: Friedman Julius J.
Published: December 2017

The time required for the vascular-extravascular equilibration of albumin in various tissues of the mouse was determined. Radioiodoalbumin was injected intravenously and tissues were sampled at intervals of 5–720 minutes postinjection by freezing the mice in liquid nitrogen. Vascular-extravascular equilibration of radioiodoalbumin in plasma occurred at about 1 1/2 hours postinjection. The vascular-extravascular equilibration of radioiodoalbumin in the tissues occurred at approximately 45 minutes postinjection in the liver and intestine, 1 1/2 hours postinjection in the muscle, and about 2 hours postinjection in the kidney, spleen, and lung. Vascular-extravascular equilibration of radioiodoalbumin in the skin had not occurred within the 12 hours postinjection period of analysis.
Influence of Differential Aortic Perfusion Pressures in Experimental Shock
Authors: Smith James J. , Grace Robert A.
Published: December 2017

A combined hemorrhagic—aortic occlusion shock was produced in dogs in order to study the effect of perfusion pressures in different aortic segments on the development of irreversible shock. Oxygen saturations of arterial, hepatic venous and inferior vena caval blood were determined before, during and after the shock procedure in order to assess the degree of anoxia prevailing in the different body segments. Perfusion of the thoracic aorta plus the coeliac and superior mesenteric arteries at 80 mm Hg mean pressure and the remaining abdominal aorta at 30 mm Hg for 2 1/2 hours resulted in lowered mortality and increased survival time compared with control groups in which conditions were similar except that the two upper abdominal arteries were perfused at the lower pressure. The protective effect of perfusion of the liver and upper splanchnic organs appears to be a specific one, i.e. not solely attributable to the decreased ischemic tissue mass involved. Mortality and survival in shock resulting from infradiaphragmatic aortic hypotension of 30 mm Hg for 2 1/2 hours was unaffected by variations in supradiaphragmatic aortic pressure within the range of 60–100 mm Hg.
Changes in Cell and Plasma Volumes of Various Organs Produced by a Massive Transfusion in Dogs
Authors: Deavers S. , Huggins R. A. , Smith E. L.
Published: December 2017

Dogs anesthetized with morphine and sodium pentobarbital were killed by bleeding or with sodium pentobarbital. The control group did not receive a transfusion; the other group was given a transfusion of blood (10.0–14.9% of the body weight). The red cell volume was measured with radioactive Cr51 and the plasma volume with I131. The volume of red cells and plasma per gram of tissue and organ were calculated for: liver, spleen, kidney, heart, lung, stomach, intestine, muscle and skin. With transfusion there was an increase in the red cell volume per gram of tissue and organ except for the spleen. The liver was the primary site of trapped cells. All tissues of the transfused dogs contained more plasma than the controls. Every organ of the control dogs contained ‘extra’ plasma (that portion of the plasma free from cells); with transfusion the volume increased and represented a greater portion of the total organ blood volume. Good agreement was found between the calculation of trapped cells and plasma from blood volume measurements and by tissue analysis.
Distribution of Red Cells and Plasma in the Dog
Authors: Huggins R. A. , Smith E. L. , Deavers S.
Published: December 2017

Two questions are examined: a) is the venous hematocrit a representative sample of the percentage of red cells to plasma in the circulation, and b) does the distribution of red cells and plasma remain constant with changes in blood volume? The dogs were anesthetized with a morphine-pentobarbital combination. Red cell volume was measured with either radioactive Cr51 or Fe59 and plasma volume with Evans blue or radioactive I131. The distribution of cells was expressed by the ratio BH/VH and of plasma by (100-BH)/(100-VH). The body hematocrit (BH) was significantly less than the venous hematocrit (VH) for 60 control dogs, and the distribution of red cells, expressed by the ratio BH/VH, was 0.90 and for the plasma 1.09. Transfusion of blood (100– 149 cc/kg, group III) was followed by a significant shift from the control value in the distribution of plasma but not of red cells. Neither hemorrhage of 15% of the estimated blood volume, reinfusion of the blood nor successive transfusion into group III was followed by a significant change in the distribution of red cells and plasma from the control distribution. With a large hemorrhage 58% of the measured blood volume and shock there was a significant shift in the distribution of red cells (0.795) from the control value. Since changes in blood volume may accompany a shift in the cell-plasma distribution, the cell or plasma volume, venous hematocrit, and a factor cannot be used for measuring blood volume unless the factor is determined for the circulatory condition being studied. Following this work we reconsidered the effect of these data on previously published work from this laboratory. Some of the absolute values were significantly altered but not the direction or percentage change.
Esterase and Clotting Activity Derived From Purified Prothrombin
Authors: Seegers Walter H. , Landaburu Ricardo H.
Published: December 2017

Purified prothrombin can be activated in several ways to obtain biothrombin. This thrombin possesses the properties of activating fibrinogen, catalyzing the activation of prothrombin, neuralizing antithrombin, dissolving fibrin clots and has esterase activity. In 0.05 m calcium solutions prothrombin activates to yield first and later predominantly esterase activity. Prothrombin preparations dried and stored for 5 years and then dissolved in 0.05 m calcium solutions yield almost exclusively esterase activity and very little activity for the clotting of fibrinogen. The esterase activity obtained from prothrombin is not equated with the clotting activity. It is possible to have only esterase activity or esterase with clotting activity. When the material derived from prothrombin possesses only esterase activity it is called esterase thrombin. Esterase thrombin can also be obtained from biothrombin by simply allowing biothrombin solutions to stand at room temperature a few days or by using chemicals such as ninhydrin. Esterase thrombin does not catalyze the conversion of prothrombin to thrombin but does dissolve fibrin clots, and although it interacts with antithrombin the kinetics are not the same as with biothrombin.
Healing Bone Fractures and Simultaneous Administration of Radioisotopes of Sulfur, Calcium and Yttrium
Authors: MacDonald N. S. , Lorick P. C. , Petriello L. I.
Published: December 2017

A mixture of carrier-free radioisotopes, Ca45, S35 and Y91, was injected into rats bearing left tibial fractures, in states of repair varying from 3–18 days. Twenty-four hours after injection, both tibias were removed and analyzed for content of each radioisotope. At all intervals up to 18 days, postfracture, the injured bone contained more of all three isotopes than the intact, contralateral mate. A maximum in 24 hour retention of radiosulfate in tissue at the fracture site, was reached by the 7th to 10th day, after which retentions of a dose of S35 declined rapidly. Retentions of a dose of Ca45 in the fractured bone also rose rapidly during the first 3–10 days of healing. Thereafter, 24 hour retention values continued to rise but at a reduced pace. The avidity of healing bone for yttrium increased sharply during the same 3–10 day interval during which radiosulfate deposition became most effective. After this time 24-hour retention values for Y91 increased only slightly, if at all. The data suggest that formation of the sulfated mucopolysaccharides of osteoid matrix and fibrocartilaginous callus began by at least the 3rd day, if not earlier. The healing fracture made its greatest demands for plasma sulfate during the 7th to 10th day, postfracture. New calcium was laid down at the fracture site just as early as new sulfate, but the demands for plasma Ca continued throughout the 18 days of observation, as might be expected for a mineralizing callus. Yttrium fixation in the healing bone appeared to be more closely related to events leading to organic matrix formation than to mineralization of the new tissue.