bluuebunny/crossref_metadata_2025 huggingface dataset:
Conversion of Prothrombin to Autoprothrombin II (Platelet Cofactor II) and Its Relation to the Blood Clotting Mechanisms
Authors: Seegers Walter H. , Johnson Shirley A.
Published: December 2017

Under certain restricted conditions purified thrombin can be added to purified prothrombin and the latter transforms to a derivative called autoprothrombin II. Except in 25% sodium citrate solution, it has not been converted to thrombin. It functions as a cofactor with purified platelet factor 3 in the conversion of prothrombin to thrombin. Serum from healthy persons and in hemophilia A contains autoprothrombin II activity that can be adsorbed on BaCO3. Autoprothrombin II, prepared in the laboratory, can be added to the two types of adsorbed serum and the autoprothrombin II activity is restored to the serum. Serum from PTA patient, and a patient receiving dicumarol was found to contain very little autoprothrombin II activity. By adding an appropriate quantity of autoprothrombin II, prepared in the laboratory, the autoprothrombin II activity of the PTC serum was not completely restored whereas it was with the other two serum samples.
Mesenteric Blood Flow as Influenced by Progressive Hypercapnia
Authors: Brickner Eugene W. , Dowds E. Grant , Willitts Bruce , Selkurt Ewald E.
Published: December 2017

The influence of hypercapnia on mesenteric blood flow was studied in dogs subjected to progressive increments in CO2 content of inspired air produced by rebreathing from a large spirometer. Oxygen content was maintained above 21 volumes %. Although some animals showed an initial tendency for mesenteric blood flow to decrease and arterial pressure to increase in the range 0–5 volumes % of CO2, the usual hemodynamic change in the range 5–16 volumes % was an increase in mesenteric blood flow resulting from decrease in intestinal vascular resistance, accompanied by a decline in arterial pressure. Portal venous pressure was progressively elevated. Heart rate slowed in association with an increase in pulse pressure. The observations suggest that in higher ranges of hypercapnia, CO2 has a direct dilating action on the mesenteric vasculature.
Influence of Cycle Length Upon Refractory Period of Auricles, Ventricles, and A-V Node in the Dog
Authors: Mendez Carlos , Gruhzit Carl C. , Moe Gordon K.
Published: December 2017

The functional refractory periods (FRP) of auricular and ventricular muscle, and of the A-V transmission system were estimated in the denervated dog heart. In all three tissues the FRP was found to be a curvilinear function of the immediately preceding cycle length, with values for all but very early premature beats falling close to the curve describing the basic cycles; that is, there was no evidence for a cumulative effect of frequency. In the auricle, the FRP of even the earliest possible premature beats appeared to fit the curve relating cycle length to refractory period. In both the A-V node and ventricles very early responses deviated from an otherwise smooth relationship. It is postulated that the deviations may represent dissociation of the properties of two different elements in each of these tissues.
Effects of Anorexia and X-Irradiation on Vitamin B6 Excretion in Rats
Authors: Song Chung Suk , Pearson William N. , Darby William J.
Published: December 2017

Adult female albino Sprague-Dawley rats subjected to 500 r (backscatter) of whole-body x-irradiation exhibit an increase in the urinary excretion of the B6 group of vitamins beginning on the 2nd day after irradiation. However, control animals, whose food intake was limited to that of the irradiated group, excreted amounts of vitamin B6 that were quantitatively similar. It is concluded that the increase of vitamin B6 excretion found after x-irradiation is a reflection of the irradiation-induced anorexia and is not due to tissue changes brought about by irradiation per se.
Effect of High-Intensity X-Radiation on the A Group Fibers of the Frog's Sciatic Nerve
Authors: Gerstner Herbert B.
Published: December 2017

Isolated sciatic nerves of bullfrogs received x-radiation at a dose rate of 9 kr/min. Prior to and following exposure, the monophasic action potential was recorded. In alpha fibers, doses between 75 kr and 200 kr caused a decrease in conduction velocity, an increase in the rise time of the action potential, and an elevated rheobase with shortened chronaxie; the potential amplitude was not obviously affected. In the dose range above 200 kr, the potential amplitude declined rapidly and complete failure of function occurred at about 300 kr. Beta fibers closely resembled alpha fibers in behavior; however, they appeared to be somewhat more radioresistant than a portion of the alpha subdivision. Gamma fibers seemed to be most susceptible to ionizing radiation; their potential disappeared at doses between 150 kr and 200 kr.
In Vivo Effect of Heparin on Acid and Alkaline Ribonuclease Activities of Mouse Liver
Authors: Lamirande Gaston De , Weber George , Cantero Antonio
Published: December 2017

A single dose of 30 µg/gm body weight of depo-heparin was injected subcutaneously into white Swiss mice. At 1, 3, 6 and 12 hours after the injection, the blood coagulation time was measured and the activity of acid and alkaline ribonuclease of liver was determined. This single injection of depo-heparin significantly inhibited the acid and alkaline ribonucleases of liver 1 hour after injection. The enzymatic activities significantly increased after the blood coagulability was restored. The in vivo inhibition of acid and alkaline ribonuclease activity supports the explanation that the accumulation of ribonucleic acid in cells of tissue culture in the presence of heparin might be due to the inhibition of ribonuclease.
Effect of Thyroid-Active Substances on the Betaine-Homocysteine Transmethylase Activity of Rat Liver
Authors: Harper A. E. , Ericson L. E. , Boldt R. E. , Elvehjem C. A.
Published: December 2017

The incorporation of iodinated casein or desiccated thyroid into the diets of rats, or the subcutaneous injection of l-thyroxine, caused a decrease in the liver betaine-homocysteine transmethylase activity. Supplementation with dried, defatted pork partially counteracted the effect of iodinated casein.
Renal Excretion of Inulin, Creatinine and Ferrocyanide, at Normal and Reduced Clearance Levels in the Dog
Authors: Ladd Michael , Liddle Lois , Gagnon John A.
Published: December 2017

In 54 control periods in 15 normal (anesthetized) dogs, the ratios of the clearances of creatinine and ferrocyanide to inulin (Ccr/Cin and Cfer/Cin) differed significantly from unity, averaging 0.936 ± 0.047 and 0.932 ± 0.059, respectively. However, in these animals, clearance ratios did not vary with Cin, or urine flow, provided that Cin exceeded 2.3 ml/min/kg (lower limit of ‘normal’). In these 15 dogs, Cin varied directly with perfusion pressure, when the latter was transiently reduced by either hexamethonium, hemorrhage or aortic occlusion. Values for Cin below 2.3 ml/min/kg were associated with decreased ratios for Ccr/Cin and Cfer/Cin. This phenomenon was uninfluenced by phloridzin or probenecid, was potentiated by urinary concentration, and (at low clearance levels) was obliterated by elevating urine flow relative to Cin. Clearance deficits quickly and permanently disappeared when Cin was elevated above 2.3 ml/min/kg by restoration of perfusion pressure. Aberrant clearance ratios cannot easily be attributed to tubular damage because they were so promptly and permanently reversed, no histological evidence of immediate or delayed tubular necrosis followed their demonstration, and in six dogs with frank tubular necrosis following HgCl2, or clamping the renal artery, no clearance deficits accompanied comparable reductions in clearance level. The observed direct relationship between clearance ratios and Cin or urine flow, must therefore reflect partial permeability of the normal renal tubule allowing passive back diffusion of at least creatinine and ferrocyanide. In the normal dog, clearance values should probably be interpreted with caution at levels for Cin below 2.0 ml/min/kg.
Creatinine Secretion by the Frog Renal Tubule
Authors: Swanson Robert E.
Published: December 2017

Simultaneous creatinine and inulin clearance measurements were carried out in Ringer-perfused and intact kidneys of the bullfrog ( R. catesbiana). For the perfusion series the median creatinine/inulin clearance ratio was 1.27. The ratio was elevated above unity for the majority of intact kidney experiments. Perfusion with poisons such as phlorizin, sodium azide, sodium arsenite and 2, 4-dinitrophenol, as well as elevation of the creatinine concentration in perfusing fluids, generally depressed the clearance ratio toward unity. It is concluded that a portion of the urinary creatinine of bullfrogs can be excreted by active tubular participation.
Influence of Temperature and Rate on the Contractility of Isolated Turtle Myocardium
Authors: Katzung B. , Farah A.
Published: December 2017

The effects of changes in rate of stimulation on contractile force of turtle myocardium were studied at various temperatures. At 38°C an increase in rate produced an increase in the contractile force (positive treppe). At 14°C increasing the rate produced a decrease in the contractile force (negative treppe). At intermediate temperatures an increase in rate produced first a positive followed by a negative treppe. Under anaerobic conditions the results were qualitatively the same although contractility was reduced by 50–75%. The increase in contractile force seen after an episode of rapid stimulation (poststimulation contraction) was studied at different temperatures. An increase in the rapid stimulation rate produced an increase in poststimulation potentiation at all temperatures studied except at 14°C where an increase in rate produced a decrease in potentiation. Some of these results can be explained on the basis of energy production which is probably depressed at low temperatures. On the other hand some other factor related to rate of stimulation must influence contractile force. This factor may be related to the active state of A. V. Hill or may be related to ionic movements postulated by Hajdu and Szent-Gyorgyi.
Carotid Blood Pressure in Normal and Tumor-Bearing Mice
Authors: Pradhan Sachindra N. , Achinstein Betty , Shear Murray J.
Published: December 2017

Blood pressure was measured directly in mice after cannulation of the carotid artery. The anesthetic was urethan in a single intraperitoneal dose of 1.4–1.6 mg/gm. The apparatus was a Technitrol Lilly manometer, or a Statham physiological transducer (Model P 23 D) with a Brush ‘Universal analyzer.’ The blood pressure was continuously recorded in some 400 CAF1 mice, both normal and bearers of Sarcoma 37. In 166 mice without tumor, the mean blood pressure varied from 35–110 mm of mercury; the average was 71 with a S.E. of ± 1. In 233 mice bearing 6-day-old implants of Sarcoma 37, the pressure varied from 40–110 mm.; the average was 78 ± 1 mm. Under these conditions of continuous recording of arterial blood pressure, about 40% of the animals lived for 2 hours; a few survived as long as 6 hours. The various patterns of blood pressure changes are described and illustrated.
Influence of Calcium on Potassium Concentration in Rat Liver in Vitro
Authors: Geyer Robert P. , Sholtz Katherine J. , Bowie Ethel J.
Published: December 2017

Page 488: Robert P. Geyer, Katherine J. Sholtz and Ethel J. Bowie, "Influence of Calcium on Potassium Concentration in Rat Liver in Vitro." Line II, column I: 112 mEq Na/l. should read 152 mEq Na/l.
Blocking of the Intrahepatic Blood Circulation. II
Authors: Popper H. L. , Jefferson N. C. , Necheles H.
Published: December 2017

In previous work it was found that a relatively small collateral blood supply by the phrenic arteries mainly was adequate to maintain the liver following ligation of the hepatic artery and the portal vein. In order to demonstrate the pathways of the collaterals, normal dogs and dogs that had survived ligation of either the hepatic artery or the portal vein for some time were used. A plastic dissolved in acetone that gelled with water, or mineral oil, or red lead dye suspension, was used for injection. The acetone content of the plastic medium produced toxic reactions. The media were injected into branches of the intact portal vein or into the intact hepatic artery, or into the hepatic artery or the portal vein above the ligature. Blocking of the intrahepatic branches of the hepatic artery caused liver necrosis in every instance, while blocking of the intrahepatic branches of the portal vein was tolerated. Thus, blocking of branches of the hepatic artery demonstrates that the essential collateral arterial blood supply had been interrupted.
Pulmonary Red Cell and Plasma Volumes and Pulmonary Hematocrit in the Normal Dog
Authors: Rapaport Elliot , Kuida Hiroshi , Haynes Florence W. , Dexter Lewis
Published: December 2017

Cr51-labeled red cells and Evans blue dye were used to measure cardiac output, circulating pulmonary and total red cell volumes, plasma volumes and resultant pulmonary and body hematocrits in nembutalized dogs. The pulmonary blood volumes were measured simultaneously by the mean circulation time-output, slope output and arteriovenous equilibration methods and averaged 210, 136 and 151 cc/10 kg, respectively, representing 28.6, 18.7 and 20.4% of the total blood volume. Pulmonary hematocrits averaged 37.6, 36.8 and 33.5%, respectively, compared to mean large vessel hematocrit of 39.7%. Total blood volume averaged 736 cc/10 kg. The mean of the ratios of body to large vessel hematocrit was .92. Cardiac outputs determined from plasma and red cell indicator dilution curves were in good agreement. The mean circulation time of red cells was consistently shorter and the exponential washout slope consistently steeper than of plasma. These differences resulted in a larger calculated total pulmonary volume by the mean circulation time and slope output methods using a plasma compared with a red cell tag; the resultant pulmonary hematocrits were significantly lower than large vessel hematocrits. The pulmonary hematocrits determined by the arteriovenous equilibration method were still lower than those calculated with the other methods. The explanation of this is uncertain. The demonstration by all three methods of a pulmonary hematocrit significantly lower than large vessel hematocrit indicates that the pulmonary bed participates in the lowering by capillary blood of large vessel hematocrit.
Relative Effectiveness of Certain Drugs Against Shock Produced in Mice From Tourniquet and Burn Trauma
Authors: Millican R. Carl , Stohlman Edward F.
Published: December 2017

The therapeutic effectiveness of chlorpromazine, dibenamine, l-norepinephrine, 1-ethylsulfonyl-4-ethyl-piperazine hydrochloride, serotonin, ascorbic acid, human plasma cholinesterase and a bacterial polysaccharide (Piromen), has been studied in experimental tourniquet and burn shock in mice. Employing survival as an indication of therapeutic effect, simultaneous comparisons were made of the survival of groups of animals receiving these agents in saline and control groups receiving saline alone. Chlorpromazine pretreatment (8–20 mg/kg) produced reproducible positive effects on survival whether given alone or in conjunction with saline replacement therapy. Dibenamine pretreatment (5–25 mg/kg) produced positive effects on survival but this response was not always reproducible. No beneficial effect was demonstrable following administration of the remainder of these agents when compared to control groups given saline alone.
Body Fat Accumulation in the Guinea Pig
Authors: Pitts Grover C.
Published: December 2017

Seventy-two guinea pig carcasses divided into three series: a) adult, b) growth (4 days to 8 months) and c) exercise (adults on an exercise regimen) were separated into eleven gross body components by dissection. Each component was freeze dried and extracted with ethyl and petroleum ether. Distribution of fat and the fat content of the gross components were studied statistically. Accretion of fat in all three series is accomplished primarily by saturating existing adipose tissue, and secondarily by an increase in either number or size of lipocytes. Females have an appreciably larger fat storage capacity than males without resorting to either lipocyte proliferation or hypertrophy. Except in immature individuals the fraction of total body fat in subcutaneous and in internal depots is constant at all levels of body fatness. Males have 6–7% less of their total fat in the subcutaneous depot and proportionately more in the internal depots than do females. Fat depots account for about 95% of total body fat, most of the remainder being distributed among gut, bone, liver, kidneys and heart. In all three series with increasing body fatness these organs acquire additional fat, but in each case the rate of fat accretion is less than that of the body as a whole. Fat distribution to the organs appears similar in the two sexes. Body fatness in the adult series was shown to be related to specific gravity of the eviscerated carcass by the following equation: (See PDF)
Transport of Cortisol-4-C14 and Progesterone-4-C14 by Serum Proteins as Demonstrated by Paper Electrophoresis and Paper Chromatography
Authors: Westphal Ulrich , Firschein Hilliard E. , Pearce Eli M.
Published: December 2017

Interaction between low concentrations of cortisol-4-C14 or progesterone-4-C14 and serum proteins was investigated by paper-electrophoretic methods in human serum albumin solution as well as in human and rat serum. Between 2 and 10% of cortisol and between 70 and 90% of progesterone were found to be bound and thus transported by human albumin. Similar transport values were observed in paper-chromatographic studies in which the steroids migrated in aqueous solution, in the presence and absence of serum proteins. A critical evaluation was made on the use of paper-electrophoretic procedures in protein-binding studies. The demonstration of a firm albumin binding of progesterone, and a comparatively loose attachment of cortisol, is in general agreement with results obtained by ultracentrifugation and ‘free’ electrophoresis. Some physiological implications are mentioned.
Pregnancy in the Little Brown Bat
Authors: Smith Elizabeth
Published: December 2017

Body weights of bats of the species Myotis lucifugus lucifugis increase exponentially during pregnancy. The rate of increase differs with the year. At birth the single offspring weighs 28.8% of the mother's weight. The metabolic rate increases fivefold during pregnancy but is always less than the expected metabolic rate for a nonpregnant mammal of the same weight. The heat increment of gestation is 2.2 kcal, an amount less than would be expected from the birth weight. The bat fetus is produced at a very low cost that is spread over a relatively long period.
Effect of in Vitro Administration of Thyroxine and Triiodothyronine on Surviving Liver Slices
Authors: Weiss A. Kurt
Published: December 2017

Liver slices from frog, turtle, guinea pig, greyhound and man were incubated in Krebs-Ringer-Phosphate medium and their oxygen uptake determined manometrically. The addition of l-thyroxine or l-triiodothyronine to the suspension medium did not produce an increased oxygen consumption.
Free Amino Acid Patterns of Certain Tissues From Potassium and/or Protein-Deficient Rats
Authors: Iacobellis Michael , Muntwyler Edward , Dodgen Charles L.
Published: December 2017

Tracings of amino acid patterns obtained chromatographically on the tungstic acid filtrates of skeletal muscle, diaphragm, kidney and liver from normal, and protein- and/or K-deficient rats have been presented. Also presented were the tracings of amino acid patterns of the same tissues from rats maintained on a control and a low-K diet and administered DCA. Evidence was presented indicating that the amino acids lysine and arginine were increased in the skeletal muscle, diaphragm and kidney from rats with K deficiency, with or without DCA administration. Concomitant to these changes, there appeared to be a decreased concentration of the amino acids aspartic acid and glutamic acid. The amino acid pattern of the liver from K-deficient rats remained essentially normal. The administration of a KCl solution by stomach tube during 24 hours to the K-deficient rats resulted in a normalization of the amino acid patterns. The amino acid patterns of skeletal muscle, diaphragm and kidney from protein- and K-deficient rats were found to be normal. However, the amino acid patterns of these tissues were found to have reverted to those observed with the K-depleted rats upon supplementing the diet of the doubly deficient animals with protein for 6 days. The significance of a possible transfer of amino acids along with a shift of H+ into muscle cells in exchange for K+ in the development of an alkalosis found in K-deficient rats was briefly commented upon.
Age and Nitrogen Content of Rabbit Brain Parts
Authors: Kelley Barbara
Published: December 2017

The nitrogen content of whole rabbit brain and seven areas, thereof, i.e. frontal cortical gray, caudate nucleus, superior colliculi, medulla, paraflocculi, vermis and lateral lobes, has been determined using 230 rabbits ranging in age from 1–70 days. In general, the percentage wet weight nitrogen content of the cerebellar areas reached a higher maximum than did that for the noncerebellar areas studied. The nitrogen of whole brain rose steadily until the 50th day of age at which time it reached a plateau. In comparing the various areas it was found that with the exception of the colliculi the phylogenetically older parts reached their maximum percentage nitrogen content at an earlier age than did the more recent areas.
Effect of Electric Current on Gastric Hydrogen Ion and Chloride Ion Secretion
Authors: Rehm Warren S.
Published: December 2017

Using the chambered gastric segment preparation it was found that application of current from serosa to mucosa resulted in an increase in H+ ion production and a decrease in Cl– ion secretion. Following the application of current from serosa to mucosa the secretory rate was essentially the same as before current application. Application of current from mucosa to serosa resulted in a decrease in H+ ion secretion and during the first 10-minute period sometimes an increase and sometimes a decrease in Cl– ion output. With continued application currents from mucosa to serosa, both the H+ ion and Cl– ion secretory rates continued to decline. Following cessation of current from mucosa to serosa the secretory rate was less than before current application. The implications of these findings are discussed in the light of a theory of HCl formation.
Arterial Inflow Into the Mesenteric and Hepatic Vascular Circuits During Hemorrhagic Shock
Authors: Cull Theodore E. , Scibetta Mario P. , Selkurt Ewald E.
Published: December 2017

Mesenteric artery and hepatic artery flows were studied in dogs during a standardized hemorrhagic shock procedure. Both flows decreased in response to hemorrhage, with development of greater vascular resistance in the hepatic artery circulation. Toward the end of the hypotensive period vascular resistance in the mesenteric artery often entered a declining phase, correlated with an increase in portal venous pressure, but hepatic artery resistance increased somewhat further. On transfusion, mesenteric artery flow increased rapidly, often exceeding the control values. Portal pressure doubled, and mesenteric resistance decreased to values less than control for about 30 minutes. This may represent a phase of pooling and trapping of blood in the capillaries and venules of the mesenteric circulation favored by reduced inflow resistance, and increased outflow resistance. This was followed by a phase of increased mesenteric resistance which often persisted until the demise of the animal, although it decreased in some animals during the terminal stage. Following transfusion, hepatic artery flow increased more gradually than mesenteric artery flow and reached a peak about 1 1/2 hours post-transfusion, at a time when flow in the mesenteric artery was markedly reduced and its resistance was maximal. The mechanism of this reciprocity of flow and resistance is discussed and its relevance to the interpretation of the hepatic artery flow changes in shock is considered.
Quantitative Histochemistry of the Dog Nephron
Authors: McCann W. P.
Published: December 2017

Microdissection techniques for the separation of different anatomical segments of the dog nephron from frozen-dried kidney sections are described. Tissue samples thus isolated were suitable for quantitative chemical and enzymatic studies by precise microchemical methods. Trypan blue used as an intravital stain, served to distinguish proximal from distal convolutions, and did not alter the enzymes studied. Quantitative comparisons of water content, lipid content, and the activities of alkaline phosphatase, aldolase, fumarase, phosphohexoisomerase and hexokinase were made. The papilla differed from the other areas in lipid content. Alkaline phosphatase was localized mainly in the proximal convoluted tubules. The other enzymes varied less regularly from area to area. Hexokinase was four times higher in the pars recta of the proximal tubule than in any other area. Inasmuch as glucose reabsorption is believed to occur in the first half of the proximal convoluted tubule, the observed distribution of hexokinase does not further the hypothesis that this enzyme is concerned in glucose reabsorption by the kidney.
Simultaneous Estimation of Plasma Volume, Red Cell Volume and Thiocyanate Space in Unanesthetized Normal and Splenectomized Rats
Authors: Huang Kee-Chang , Bondurant James H.
Published: December 2017

A method for simultaneous estimation of plasma volume, red cell volume and thiocyanate space in unanesthetized rats utilizing a polyethylene catheter in the common carotid artery with T-1824, P32-tagged red cells, and NaSCN was perfected and determinations were performed on 77 male albino rats. Determinations of plasma volume using T-1824 or I131-serum albumin in the same animal gave essentially identical results. Total blood volume was calculated as the sum of P32-red cell volume and T-1824-plasma volume and was found to be 5.75 ml/100 gm body weight in normal rats and 5.61 ml/100 gm in splenectomized rats. There was a wide variation in the Fcell values of normal rats but little in splenectomized rats. This difference was highly significant and was attributed to the presence of the spleen. The average thiocyanate space was found to be 33.0 ml and 35.8 ml/100 gm in normal and splenectomized rats, respectively.
Effect of Total Body X-Irradiation on Plasma Volume, Red Cell Volume, Blood Volume and Thiocyanate Space in Normal and Splenectomized Rats
Authors: Huang Kee-Chang , Bondurant James H.
Published: December 2017

A single dose of 600 r of x-ray was given to groups of nonanesthetized normal and splenectomized rats. Simultaneous estimations of plasma volume, red cell volume, and thiocyanate space were performed in these animals before and after x-irradiation. In normal rats plasma volume decreased in the first 8 days postirradiation but showed a significant increase by the 10th day. The reduction of red cell volume and hematocrit developed gradually and was markedly shown by the 10th day. The blood volume after irradiation was generally larger than that of the normal value. The SCN space increased on the 4th day after irradiation then decreased in the next period and was elevated again by the 10th day postirradiation. In splenectomized rats the change of SCN space was similar to that observed in normal rats and the changes of blood volume were varied. A marked reduction of red cell volume with an increase, probably compensatory, of plasma volume, developed in these rats by the 4th day after x-irradiation.
Prophylaxis Against Acute Pulmonary Edema and Death in Dogs With Aortic Insufficiency Following Renal Artery Constriction Afforded by Prior Construction of an Atrial Septal Defect
Authors: Hawthorne Edward W. , Brownlee Gwendolyn V. , Spellman Mitchell W.
Published: December 2017

Prophylaxis against acute pulmonary edema and death in dogs with aortic insufficiency following renal artery constriction by prior constriction of an atrial septal defect. Dogs with the combined cardiac lesions of atrial septal defect and aortic insufficiency were studied. The atrial septal defects were large and were produced under direct vision. The present studies indicate that when such dogs are subjected to renal artery constriction (RAC) they neither die acutely (within 2 days) nor develop acute massive pulmonary edema. These dogs develop varying patterns of ‘congestive failure’ after RAC. The severity and course of this ‘congestive failure’ seemed to depend upon either the size of the aortic valvular ‘leak’ or the degree of RAC produced in a particular dog.
Enlargement of the Liver in Sprague-Dawley Rats Following Whole-Body X-Irradiation
Authors: Supplee Helen , Weinman E. O. , Entenman C.
Published: December 2017

A significant increase in liver mass was observed in rats as early as 6 hours after exposure to as small a dose as 200 r of 250 kvp x-rays. Water, lipids and glycogen contribute to the increase in mass; however, the most striking change was in the glycogen content.
Electromyographic Study of Postural Muscles in Various Positions and Movements
Authors: Portnoy Harold , Morin F.
Published: December 2017

Electrical activity of ‘postural’ muscles (sacrospinales, hamstrings, gastrocnemii, quadriceps femoris) in normal subjects during different positions and movements of the body varies in different individuals. The sacrospinales become active whenever slight displacements of the center of gravity occur. The sacrospinalis of both sides participate in lateral flexion and extension, and rotation of the vertebral column. In leaning forward, these muscles (except the quadriceps) are working essentially under isometric conditions and their electrical activity is prominent. Stretch, then, appears to be a major factor for the activation of these muscles. In flexion of the trunk, the sacrospinales cease to function at a ‘critical point,’ however, further trunk flexion occurring mainly at the hip joints continues to be accompanied by the activity present in the hamstrings. In more complex movements, such as sitting and standing, the same basic mechanisms related to stretch and displacement of the center of gravity appear to hold true.
Intracellular Accumulation as an Active Process in a Mammalian Renal Transport System in Vitro
Authors: Forster Roy P. , Copenhaver J. H.
Published: December 2017

Studies on thin slices of rabbit renal cortex indicate that substances which accumulate in vitro are concentrated intracellularly without further discernible concentration in the lumen. Movement into cells of the proximal tubules is an active process dependent upon aerobic phosphorylation and subject to competitive inhibition involving p-aminohippurate, phenol red, chlorphenol red and benemid. All experimental indications are that this is the first step in the over-all transfer of these substances by renal tubules in the intact kidney.
Adrenal Influences on Distribution of Injected Colloidal Thorium
Authors: Reichard Sherwood M. , Gordon Albert S.
Published: December 2017

A chemical analysis was made of the influence of adrenalectomy upon the distribution of intravenously administered colloidal thorium dioxide (thorotrast) in spleen, liver, lymph nodes, lung, blood and urine of the adult rat. Adrenalectomy resulted in a decrease in the uptake of thorium by the spleen; this occurred as early as 2 hours and was maintained for at least 48 hours after its administration. The blood levels decreased quickly; only slight amounts remained after 2 hours. No significant differences were noted in thorium concentration within the livers of normal and adrenalectomized rats at 2, 4, 8, 24 and 48 hours after its injection. The lungs and lymph nodes (at 2 hr.) of adrenalectomized rats accepted slightly greater amounts of the metal than similar organs in control rats. Thorium was excreted in urine in slight amounts; but adrenalectomy resulted in a slightly greater excretion of ThO2/gm dried urine. Although the concentrating activity of spleen was much greater than the liver, the total amount of thorium deposited in the liver was larger. The quantities of thorium recovered from the normal rats were always greater than those from adrenalectomized animals, by a difference almost identical with that found between the spleens from normal and operated animals. The relatively large differences in thorium uptake by the spleens of normal and adrenalectomized animals cannot be accounted for by the differences in thorium deposition in other organs studied and by elimination in the urine. The discrepancy is probably explained on the basis of differential entry of thorium into tissues other than those examined in the present study.
Effect of Norepinephrine on Circulation of the Dog in Hemorrhagic Shock
Authors: Frank E. D. , Frank H. A. , Jacob S. , Weizel H. A. E. , Korman H. , Fine J.
Published: December 2017

Norepinephrine infusion did not prolong the survival or effect the recovery of dogs in hemorrhagic shock unresponsive to replacement transfusion. During its pressor action in shock, either before or after replacement transfusion, norepinephrine infusion increased coronary, cerebral and adrenal blood flow, reduced renal blood flow, and did not change hepatic blood flow. Cardiac output was increased in oligemic shock but not after blood replacement. Pulmonary arterial pressure and right and left auricular pressures were raised by norepinephrine infusion in all phases of hemorrhagic shock, and calculated pulmonary vascular resistance was reduced.
Lactic and Pyruvic Acid Relations in Contracting Mammalian Muscle
Authors: Sacks Jacob , Morton Jo H.
Published: December 2017

Tetanic contraction of mammalian muscle under essentially anaerobic conditions was found to result in marked increase in the pyruvic acid content as well as in the lactic acid content. The increase in lactic acid content was proportionately greater than in the pyruvic acid content. Repeated single twitches at a rate of 1/sec., continued long enough to produce a steady state, resulted in only a slight increase in pyruvic acid content, with a marked decrease in the ratio of pyruvic to lactic acid. The pyruvic acid formed during the steady state of activity appears not to pass into the blood stream.
Effect of an Histaminase Inhibitor (Aminoguanidine) on the Gastric Secretory Response to Exogenous Histamine
Authors: Lin T. M. , Ivy A. C. , Karvinen Esko , Ivy Emma K.
Published: December 2017

Aminoguanidine, a diamine oxidase inhibitor, in a dose of 0.4–1.0 mg/kg/ min. given intravenously during a period of from 20–25 minutes stimulates the gastric acid secretory mechanism of a Heidenhain and Ivy pouch dog secreting no free acid after a latent period of from 20–30 minutes for a period of 1–4 hours, depending on the dose. A rough dose-response relationship exists until evidences of toxicity occur at a dose of 4–5 mg/kg/min. is given. The administration of an intravenous threshold dose of aminoguanidine decidedly augments the gastric secretory response to a 0.05-mg dose of histamine diphosphate given subcutaneously to such dogs every 10 minutes. The existing evidence suggests that the augmentory effect is an additive effect due to the accumulation of histamine resulting from the action of aminoguanidine on histaminase.
A Neurohumoral Mechanism of Reticulo-Cortical Activation
Authors: Purpura Dominick P.
Published: December 2017

Cross-perfusion experiments were performed on unanesthetized intact and ‘encephale isole’ cats paralyzed with minimal amounts of succinylcholine-chloride. Stimulation of the bulbar reticular formation in one animal (donor) produced electrocortical ‘activation’ in the second (recipient) animal after 30–80 seconds. In addition to evoking typical activation patterns in the recipient animal, both facilitation and inhibition of Metrazol spikes were obtained in the recipient animal by reticular stimulation of the donor. This effect on the brain of the recipient animal is attributed to the release of a humoral agent from the brain of the first, electrically stimulated (donor) animal. The long latency effect is believed to represent elaboration of the neurohumor through intermediate stages.
Single Cell Spike Activity in the Olfactory Bulb
Authors: Walsh Raymond R.
Published: December 2017

Studies of single-cell spike discharges in the olfactory bulb of the rabbit indicate the presence of three classes of neurons as characterized by their discharge patterns. Cells of class I discharge continuously and spontaneously; class II cells discharge intermittently in bursts, in synchrony with the passage of air through the nose. Cells of classes I and II are unmodified during olfactory stimulation. It appears there are many cells in the olfactory bulb whose discharge patterns are unrelated to excitation of the olfactory receptors by odors. Cells of class III respond to appropriate odors; the response of such cells to some odors and not others indicates that odor specificity is a fundamental characteristic of the olfactory system.
Effects of Fatty Acid Anions on the Electroencephalogram of Unanesthetized Rabbits
Authors: White Richard P. , Samson Frederick E.
Published: December 2017

The i.v. injection of 4 mm/kg of buffered fatty acid anions of propionate, butyrate, valerate and caproate evoked electroencephalographic (slow high amplitude waves) and behavioral signs of sleep. The long chain fatty acid compounds were more effective than the short. On the other hand, comparable solutions of glucose, NaCl, lactate, acetone and Beta-hydroxybutyrate had no such effect. The evidence indicates that the fatty acid anion effect is mediated through the central nervous system and is not a secondary result of changes in cardiovascular physiology. CNS stimulation with amphetamine sulfate does not alter the depressant effect of the fatty acid anions.
Effects of Graded Doses of Epinephrine and of Norepinephrine on Blood Pressure Before and After Total Spinal Anesthesia
Authors: Hilton James G. , Reid Shelby C.
Published: December 2017

Experiments have been carried out on dogs anesthetized with pentobarbital sodium to determine the effects of loss of all reflexes at the spinal level upon the responses to graded doses of epinephrine and norepinephrine. Total loss of reflexes was achieved by intraspinal injection of 2% procaine hydrochloride. The results of this study showed that in both the epinephrine and norepinephrine series of animals the maximum to which the blood pressure would rise was significantly lower after total spinal anesthesia than before. The actual rise in blood pressure was significantly greater at the higher doses tested after total spinal anesthesia. At the lower doses tested the differences between responses before and after total spinal anesthesia were slight and not significant. In all cases where there was a pressor response the duration of the pressor response was longer after total spinal anesthesia. In both the epinephrine and norepinephrine series of animals the differences in duration of pressor response reached an approximately constant value at the higher dosage levels. The dose-response curves were derived for each animal and the parameters were compared. The parameter a which has been defined as the theoretical maximum pressor response was significantly greater in both the epinephrine and the norepinephrine animals after spinal anesthesia. This was the only parameter significantly affected by the total spinal anesthesia.
Activation of Prothrombin
Authors: Penner John A. , Seegers Walter H.
Published: December 2017

In the activation of a prothrombin solution, only part of the prothrombin becomes biothrombin, some becomes autoprothrombin I and some becomes autoprothrombin II. Thrombin-thrombin is also obtained, and perhaps other derivatives of prothrombin are formed. Prothrombin thus has multiple potentialities and these can be developed in diverse ways. Ac-globulin, calcium ions and platelet factor 3 can be used to obtain autoprothrombin I. Thrombin and Ac-globulin transforms prothrombin to autoprothrombin II, while platelet factor 3 or calcium ions tend to inhibit the transformation. Since calcium ions and platelet factor 3 also function as activators in one of the prothrombin to biothrombin reactions they are either activators or inhibitors of prothrombin activation depending upon the specified conditions.
Effect of Atropine on Histamine-Stimulated Gastric Secretion in the Dog
Authors: Janowitz Henry D. , Hollander Franklin
Published: December 2017

Inhibitory effect of atropine on gastric acid secretion was studied in four dogs with vagally denervated corpus pouches, stimulated by 0.025 mg of histamine-base subcutaneous every 10 minutes. The mean inhibition of acid output in the 3rd hour after subcutaneous injection of atropine sulphate was 29% at 0.1 mg/kg body weight, 31% at 0.2 mg/kg, and 96% at 0.4 mg/kg. At the highest dosage, inhibition was virtually complete in six of seven experiments. Since current concepts of cholinergic blocking action by atropine on gastric secretion are not completely explanatory of the present results, possible alternative formulations of the role of acetylcholine and histamine in stimulating the parietal cell are presented. One of these postulates that histamine is the final common chemical pathway for all stimuli to the acid secreting cell. The existing evidence for this is reviewed briefly. In addition, further striking evidence is presented to support the hypothesis that the primary (parietal cell) acidity is relatively constant and independent of the secretory rate.
Effect of Adrenal Hormones on Carbohydrate Metabolism in Riboflavin and Pantothenic Acid-Deficient Dogs
Authors: Arnrich Lotte , Nelson Mary Ruth , Gram Mary Rose , Morgan Agnes Fay
Published: December 2017

Fasting blood lactic acid levels rose 100% in 11–13 weeks in riboflavin-deficient dogs as did in lesser degree blood pyruvic acid. Eosinopenia was marked also in this deficiency but eosinophilia characterized late pantothenic acid deficiency. Swimming stress caused excessive rises in blood glucose and lactic acid in riboflavin-deficient but not in pantothenic acid-deficient and normal dogs. Marked eosinopenia was caused by swimming in the normal but not in any of the deficient animals. The normal and pantothenic acid-deficient dogs, following epinephrine treatment, showed the usual rise and fall in blood glucose and lactic acid, increased liver glycogen and marked eosinopenia. Cortisone treatment produced lowering of glucose and lactic acid blood levels in normal and riboflavin-deficient dogs but a rise in glucose in the pantothenic acid-deficient animals. Enlarged and hemorrhagic adrenals of lowered ascorbic acid content were usually found in the severely riboflavin-deficient dogs but significantly fatty livers only in the animals which had succumbed in hypoglycemic collapse. The pantothenic acid-deficient dogs had adrenals of nearly normal composition in spite of hemorrhagic lesions and moderately fatty livers. The adrenal cholesterol was normal in both deficiencies. In riboflavin-deficiency in both stressed and unstressed conditions, dogs manifest some signs of hypoxia, hypersensitivity or over-production of epinephrine but no adrenal cortical failure. Pantothenic acid-deficient dogs show little evidence of hypoxia or epinephrine sensitivity but signs of hypocorticalism.
Effect of Propylthiouracil on Degradation of I131-Labeled Thyroxine and Triiodothyronine
Authors: VanArsdel Paul P. , Williams Robert H.
Published: December 2017

Effects of antithyroid drugs on certain aspects of thyroxine and triiodothyronine metabolism in the rat were studied by measuring the tissue distribution and the excretion pattern of radioactivity following the injection of the I131-labeled hormones. Both TCA-soluble and TCA-precipitable fractions of radioactivity were assayed. In the presence of propylthiouracil, the rate of degradation of both labeled hormones was apparently slowed, as manifested by decreased urinary excretion and lower blood levels of TCA-soluble (nonhormonal) radioactivity. An increased fecal excretion of radioactivity occurred and was a result of a more rapid release of radioactivity into the bile. Potassium perchlorate, administered for 2 weeks, produced thyroidal enlargement, but had no measurable effect on the distribution or excretion of radioactivity, following labeled thyroxine administration.
Effects of Castration, Testosterone Propionate and Exposure to Cold on the Oxygen Uptake of Rat Tissues
Authors: Denison M. E. , Jasper R. L. , Hiestand W. A. , Zarrow M. X.
Published: December 2017

Oxygen uptake of liver, kidney and brain slices was determined from intact and castrated male rats exposed to cold (2 ± 2°C) and treated with either testosterone propionate or sesame oil. Rats were treated with 1 mg testosterone propionate or 0.1 cc sesame oil daily for periods of 15 and 50 days. Another group of intact and castrated rats were maintained at room temperature (23 ± 2°C) and treated similarly to the animals exposed to cold. The oxygen uptake of the tissue slices was compared to that observed in tissue slices from control rats receiving no treatment. Castration caused an increase in oxygen uptake and treatment with testosterone propionate caused a decrease. Treatment of intact and castrated rats with testosterone propionate during cold exposure resulted in increased oxygen uptake. Sesame oil alone, likewise, resulted in increased oxygen uptake of liver and brain slices from castrated rats treated during cold exposure. The oxygen uptake of kidney slices from castrated rats was not affected by exposure to cold.
Nature of the Inhibition of Thrombin Formation by Sulfhydryl-Oxidizing Agents
Authors: Koppel J. L. , Mueller Dorothy , Olwin John H.
Published: December 2017

Thrombin formation has been shown to be inhibited by oxidized glutathione and other sulfhydryl-oxidizing agents. This effect is observed with purified bovine prothrombin and with prothrombin as present in human plasma. It is different in nature from a similar inhibition brought about by sulfhydryl-containing (reducing) substances. Experiments with purified clotting factors and a variety of plasma and serum preparations have been carried out in order to elucidate the nature of the inhibition produced by SH-oxidizing substances. The results obtained indicate that thrombin formation is inhibited by these reagents as a result of their reaction with Ac-globulin sulfhydryl groups leading to partial or complete inactivation of this accelerator.
Electrical Alternans in Single Ventricular Fibers of the Frog Heart
Authors: Kleinfeld Morris , Stein Edward , Magin John
Published: December 2017

Electrical alternation was produced in single ventricular fibers of the frog heart in 14 experiments by means of l-thyroxine, triiodothyronine and acute anoxia. The phenomenon was transitory, unrelated to heart rate, and more often than not associated with decreased cardiac contractility. Four types were observed: alternation in a) the rate of depolarization, b) the rate of repolarization, c) the magnitude of the action potential and d) hyperpolarization. Usually the alternation involved several phases of the membrane action potential. The exact mechanism by which the agents used produced the phenomenon is unknown.
Effect of Corticoids on the Resistance of the Kidney to an Excess of Phosphates
Authors: Selye Hans , Bois Pierre
Published: December 2017

In unilaterally nephrectomized rats, the substitution of 1.2% NaH2PO4 for drinking water rapidly produced marked calcium deposition in the pars intermedia of the kidney. This effect of the phosphate solution is enhanced by concurrent treatment with desoxycorticosterone acetate (DCA) and inhibited by cortisol acetate (COLA). The possible rôle of corticoids in the production of clinical nephrocalcinosis and renal calculus formation is briefly discussed.