bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Physiologic Acids on Electrolytes in Rat Diaphragm
Authors: Rogers Terence A. , Wachenfeld Anne E.
Published: December 2017

The effects of physiologic acids on muscle electrolytes were studied by incubating rat hemidiaphragms in Krebs-Ringer solution or blood at pH 7.4 and 6.8. With the addition of acetic, lactic or beta-hydroxybutyric acid to depress the pH, the sodium and potassium contents of muscles incubated in Krebs-Ringer solution were the same at each pH. This is in contrast to the efflux of these cations previously observed on adding hydrochloric acid to this medium. Using heparinized rat blood as the medium, the effect of hydrochloric acid was the same as in Krebs-Ringer solution. With acetic acid however, the pattern was reversed. Muscles in blood acidified with acetic acid actually retained more potassium than the controls at pH 7.4. An increased Pco2 to depress the pH in blood did not affect the potassium content, but there was a gain of sodium in the muscles in the more acid blood so that the net cation content increased. In contrast to the physiologic acids which can penetrate the cells as intact molecules, hydrochloric acid produces an essentially extracellular acidosis. Hydrochloric acid therefore causes a displacement of intracellular cation as hydrogen ions penetrate the cell. With blood, which is better buffered than the intracellular fluid, acetic acid and carbon dioxide depress the intracellular pH more than the extracellular pH. The pH gradient across the membrane is then analogous to that with hydrochloric acid but in the opposite direction resulting in a movement of cations into the cells.
Basic Amino Acids as Intracellular Cations in K Deficiency
Authors: Eckel Robert E. , Norris James E. C. , Pope Charles E.
Published: December 2017

Rats were made K deficient by diet, by the injection of desoxycorticosterone acetate, and by protein repletion of protein depleted rats fed K-free diets. The tissues were examined for increases in basic amino acids. Increased amounts of l (+) lysine, identified by chromatographic, electrophoretic, enzymatic and microbiological techniques have been found in the muscle and kidney of K-deficient animals. The lysine and/or the basic amino acid content as well as the Na, K and Cl content of muscle and plasma has been measured. Lysine contributes significantly to the total cations of muscle in K deficiency. On partial K repletion, some of this lysine is apparently completely oxidized.
Influence of Lysine and NH4Cl Feeding on the Electrolytes of Normal and K-Deficient Rats
Authors: Eckel Robert E. , Pope Charles E. , Norris James E. C.
Published: December 2017

Control and K-deficient diets supplemented with lysine HCl and NH4Cl have been fed to rats for 2 or 3 weeks and the tissue and urine electrolytes studied. Lysine when fed in the control diet accumulates in muscle without depletion of muscle K. The lysine accumulation of dietary K depletion is accentuated by lysine feeding and diminished by NH4Cl feeding. Both supplements to the K deficient diet increase urinary K loss. It is concluded that lysine does not compete with K either for entrance into the muscle cell or at the renal level.
Localization of Nephron Transport by Stop Flow Analysis
Authors: Malvin Richard L. , Wilde Walter S. , Sullivan Lawrence P.
Published: December 2017

Localization of transtubular transport of substances along the nephrons of a pentobarbitalized dog is characterized by allowing concentration patterns to develop during stopped tubular flow (ureteral occlusion with stopped filtration). Previous administration of an osmotic diuretic mannitol provides a watery menstruum against which characteristic concentration patterns are developed point to point along the nephrons. On release of occlusion the diuretic flush washes the concentration pattern along each nephron. Serial urine samples, delivered from a polyethylene catheter, segment this pattern into an ordered array. Plots against time show distortion of the concentration pattern due to variable flow rate. The filtration indicator inulin is injected late after occlusion to reach the filter surfaces and to signal new entry of filtrate into the urine samples after the occlusion is released. The rising concentration pattern of this inulin delineates the randomizing effect of variable lengths among nephrons. Para-aminohippurate (PAH) injected after occlusion signals entry sites for secretion. These appear ahead of inulin. If glucosuria is developed before occlusion such that the glucose reabsorptive transfer maximum is exceeded, the occlusion now allows further time for lowering of glucose concentration along the tubule. The lowered glucose concentration pattern overlaps that of rising PAH, the PAH here being continuously infused beginning before occlusion. PAH secretion is proximal in the mammal. Very distal fluid is relatively sodium free; Na concentrations in proximal areas are not lowered below that accomplished during free diuretic flow. Phosphate shows only reabsorption and a proximal area overlapping glucose. Total measured blood flow is unimpaired during 8-minute occlusions. Plasma PAH extraction ratios are unchanged. Postocclusively injected K42 and Na24 reach all stop flow samples. Evidently peritubular blood flow continues to reach all points along the nephron.
Effects of Histamine, 5 Hydroxytryptamine and Epinephrine on Pulmonary Hemodynamics With Particular Reference to Arterial and Venous Segment Resistances
Authors: Gilbert Robert P. , Hinshaw Lerner B. , Kuida Hiroshi , Visscher Maurice B.
Published: December 2017

Studies were made of the effects of histamine and 5 hydroxytryptamine (5HT) on arterial and venous segmental resistances in the isolated perfused dog lung. The lung was perfused at constant flow while pressures were measured in the pulmonary artery (PA), left atrium (PV) and in either the pulmonary artery wedge position (PAw) or a small pulmonary vein (PVs). Arterial resistance changes were inferred from changes in the PA-PAw pressure drop, and venous resistance from the PAw-PV pressure gradient. Changes in lung weight were recorded continuously. It was found that histamine usually caused a greater increase of the venous resistance than of the arterial resistance, while 5HT usually increased the arterial resistance more than the venous resistance. When the predominant resistance increase was arterial the lung weight fell, but when there was a sizeable increase of the venous resistance the lung weight rose, presumably as a result of increased capillary blood content. The correlation coefficient between the change in lung weight and the change in venous resistance was + .791. Small pulmonary vein pressures rose after administration of epinephrine, norepinephrine, histamine and 5HT. This result gives further proof of constriction of pulmonary veins by these agents.
Physiologic Factors Which Influence Acidophilia Induced by Stressors in the Chicken
Authors: Newcomer W. S.
Published: December 2017

Application of cold (4°C) together with wetness, acute anoxia, restraint or injection of saline (0.2 ml), epinephrine (0.2 mg), histamine (0.2 mg), or formaldehyde (0.2 ml, 40%) was followed by an acidophilia in white leghorn cockerels within 4–8 hours; acidophilia which followed injection of cortisone, hydrocortisone, desoxycorticosterone and aldosterone is consistent with the supposition that the above stressors activate the adrenocortical tissue of the chicken. Hypophysectomy markedly inhibited but did not wholly prevent the acidophilia which followed restraint therefore a nonpituitary factor is probably involved in stressor-induced acidophilia. This latter factor could be epinephrine but is probably not histamine since prior injection of antihistaminic agents did not inhibit restraint-induced acidophilia.
Cardiovascular Reactivity of Recently Nephrectomized Dogs Receiving Peritoneal Lavage
Authors: Krieger E. M. , Hamilton W. F.
Published: December 2017

Seventeen dogs, kept in excellent clinical condition by means of peritoneal lavage, were studied before and after unilateral and bilateral nephrectomy. Heart rate, cardiac output, arterial pressure and total peripheral resistance were measured by the pulse contour method, validated for cardiac output against the dye injection method in the renoprival state. These same measurements were made at the peak of the pressure response to a battery of pressor stimuli including epinephrine, levarterenol, central vagus stimulation and ganglionic stimulation. Twelve normal dogs were subjected to insulin glucose infusion, reducing serum potassium levels below normal, and given the same cardiovascular reactivity tests. The resting hemodynamics of the nephrectomized animals was quite abnormal though the arterial pressure was normal. After both unilateral and bilateral nephrectomy the total peripheral resistance was significantly reduced and the flow greatly increased. In response to pressor stimuli there was an increase in arterial pressure and resistance and a reduction in flow. These changes were significantly augmented in the renoprival state but not after unilateral nephrectomy. The responses to pressor stimuli were greatly diminished by lowered serum potassium levels in 1 nephrectomized dog and in 12 normal dogs. The effect of the change in potassium levels was diminished by vagotomy and ganglionic blockade.
Metabolic Factors in the Development of Homeothermy in Dogs
Authors: McIntyre Donald G. , Ederstrom H. E.
Published: December 2017

Dogs from 1 to 25 days of age were exposed to air temperatures of 5, 23 and 30°C and their oxygen consumption measured in a closed calorimeter. Animals 1–5 days old had a rise of 20–25% in metabolic rate, but rectal temperature fell, when they were exposed to 5 or 23°C. At 11–21 days of age dogs exposed to 5°C had a rise of about 75% in metabolic rate, but rectal temperature fell several degrees in 1 hour. In dogs 21–25 days of age metabolic rate increased about 75% at air temperatures of 5°C and rectal temperature fell only about 1°C. Under the same conditions a trained adult dog had a rise of 80% in metabolic rate, and no fall in rectal temperature. Since heat production in 2- to 3-week-old dogs was increased to about the same extent as in the adult on cold exposure, it was assumed that heat conservation lagged behind heat production in the development of homeothermy.
Mid-Line Tissue Dose and Lethality in X-Irradiated Rats
Authors: Kereiakes J. G.
Published: December 2017

The ld50 values were determined for rats exposed to 100–250 kvp x-rays for doses expressed ‘in air’ and ‘in tissue.’ Dose measurements were made in animal tissue. For the ld50 ‘in tissue’ doses, the relative effectiveness was approximately one for all qualities. For the experimental conditions of the study, it seems that mid-line tissue dose may be the proper parameter for acute lethality in rats exposed to x-radiations having different depth dose distributions.
In Vitro Absorption of Radioiron by Everted Pouches of Rat Intestine
Authors: Brown Elmer B. , Justus Bertram W.
Published: December 2017

Everted pouches of rat intestine prepared by the technique of Wilson and associates were used to measure absorption of radioiron. Iron was taken up equally well in vitro by all segments of the rat's small intestine; but when the iron was given orally in vivo, a distinct gradient, highest in the duodenum and progressively smaller in the distal segments was demonstrated. There was little transfer into the inner serosal pouch. Transfer of iron in this preparation was by a process of passive transport. It was not appreciably affected by changes in pH, various metabolic inhibitors, buffer systems, or added substrates. Ferrous iron was significantly better taken up by the intestinal tissue, but transfer into the inner pouch fluid was greater with ferric iron.
Muscle Electrolytes in Acid and Alkaline Solutions
Authors: Fenn Wallace O. , Rogers Terence A. , Ohr Eleonore A.
Published: December 2017

Isolated frog muscles were equilibrated in solutions of varying pH and were then analyzed for potassium, sodium and sometimes chloride, phosphate, or bicarbonate. It was found that acid applied outside the muscle causes in most cases an increased loss of K. Over the physiological pH range this was also true of Na in experiments in which the complication of the extracellular space was minimized by replacing 90% of the NaCl of the solution by sucrose. In the other experiments the variations were such that it was impossible to establish any regular effect of pH on the movements of sodium. Except at a pH below 2 or above 12 the Na did not appear to exchange with K in response to injury. It is suggested that the Na pump in muscle works better when the Na is being moved into a more acid solution. It is concluded that muscle neutralizes external acid in part by loss of K, sometimes by loss of Na, and to some extent by gain of chloride. There was a slightly increased loss of phosphate and bicarbonate from muscle in the more acid solutions but no evidence of an increase in the extracellular fluid as measured by inulin.
Associated Effects of Diet, Environmental Temperature and Duration of Exposure on the Major Constituents of the Livers of Rats
Authors: Vaughan David A. , Hannon John P. , Vaughan Lucile N.
Published: December 2017

The effects of feeding pemmican and a stock diet, and of exposure to an environment of 5°C for periods of 1 month or 5 months, on the percentages of glycogen, total fat, phospholipid, protein and water in the livers of rats were studied, concomitantly. Cold exposure had the following significant effects: a) a reduction in percentage glycogen of both dietary groups, b) a reduction in percentage total fat of the pemmican group, c) an increase in phospholipid (percentage of total fat) of both dietary groups, d) an increase in percentage water of both dietary groups. The ingestion of pemmican had the following significant effects: a) a reduction in percentage glycogen, b) an increase in percentage total fat, c) an increase in phospholipid (percentage of total fat) at 27°C, d) a decrease in percentage water. Statistical analysis revealed that the effects of cold exposure and diet were dependent to a certain extent upon each other and that the duration of exposure modified the effects of both of these experimental treatments in several cases.
Epinephrine and Carbohydrate Metabolism
Authors: Drury Douglas R. , Wick Arne N.
Published: December 2017

It is generally accepted that epinephrine promotes the breakdown of muscle glycogen to lactic acid and that this lactic acid is largely reconverted to glycogen by the liver. We have re-examined this concept making use of lactate, and glucose, C14-labeled. These compounds were injected into intact rabbits after they had been given a dose of epinephrine. In this way the circulating lactate, or glucose, would be tagged and we could follow the disposal of it. We found that the lactate is very quickly oxidized to CO2 and very little is converted to glucose or glycogen. The lactate is much more quickly burned than is the glucose. The lactate set free by epinephrine serves as an important emergency fuel that can be quickly burned by the organism.
Factorial Study of Environmentally-Induced Metabolic Changes in Rats
Authors: Hale Henry B. , Mefferd Roy B.
Published: December 2017

Metabolic effects of chronic exposure to combinations of adverse environmental influences were studied in rats. During exposures lasting 12 weeks, rats were subjected to the barometric pressure equivalent to 18,000 feet altitude at temperatures ranging from 5° to 34°C. Controls at the various temperatures were held at ground level (700 ft. above sea level). Biweekly observations showed that metabolic functions (water, electrolyte and nitrogen) were influenced primarily by the thermal factors, but altitude effects could also be distinguished. Observations are reported for survival, body weight change, water and food intake, urine volume and the urinary excretion of Na, K, PO4, Mg, Ca, urea, uric acid, creatinine, taurine and 10 amino acids.
Erroneous Measurement of Plasma Volume in the Rabbit by T-1824
Authors: Zizza F. , Reeve E. B.
Published: December 2017

When measurements of plasma volume are made in rabbits with T-1824 and rabbit albumin labeled with I131, the dye value averages 1.09 of the labeled albumin value. This dye value is in error, and the probable cause is loss of a fraction of the dye from the circulation immediately after the dye injection. Comparison of the later rates of loss of T-1824 and I131-albumin from the circulation shows that the dye is lost at nearly double the rate of loss of I131-albumin. T-1824 is thus an unsatisfactory label for rabbit albumin, and cannot be used for measurements of rabbit plasma volume. When Fcells (body hematocrit/venous hematocrit) is measured with P32-labeled cells and I131-albumin the average value in rabbits is 0.895.
Pancreatic Secretion in the Rat
Authors: Grossman Morton L.
Published: December 2017

Observations have been made on male rats weighing 300–400 gm surgically prepared for total diversion of pancreatic juice to the exterior through a polyethylene cannula. While subsisting on dextrose-saline solution the rate of pancreatic secretion was about 0.15 ml/hr. in the immediate postcannulation period and rose by the 2nd day to a stable level of about 0.60 ml/hr. which persisted for at least 6 days. Rate of secretion was increased by feeding but not by introduction of stimulants such as HCl into the duodenum. Intravenous injection of secretin caused an increase in rate of secretion the magnitude of which varied with the dose of secretin. When the pancreas was made to secrete against a column of fluid 10 cm high the rate of secretion was unaltered.
Contractility of Dystrophic Mouse Muscle
Authors: Sandow Alexander , Brust Manfred
Published: December 2017

Excised gastrocnemii from 2–4-month-old normal and genetically dystrophic mice (Jackson Memorial Laboratory strains) were studied at 15°C which permits prolonged uniform maintenance of standard responses. Results are averages from muscles of generally 10–14 diseased or normal animals. Normal muscles (87 mg) produce maximal twitch and tetanus tensions of respectively 23.9 and 53.1 gm; dystrophic muscles (35 mg) correspondingly yield 3.3 and 14.6 gm. Thus, compared to normal, dystrophic muscles are atrophied, weaker (directly or in tension output/gm muscle), and show a smaller twitch/tetanus tension ratio. The contraction period time is the same for both muscle types (about 59 msec.), but the dystrophic relaxation period is 3 times longer (676 as against 224 msec.). The dystrophic active state duration (to end of plateau) is shorter than the normal (9.8 as against 14.4 msec.). At rest, both muscle types possess nonlinear elasticity, but the diseased are stiffer.
Alteration of Renal Response to Carbonic Anhydrase Inhibitor by Synthetic Adrenal Steroids
Authors: Perlmutt Joseph H. , Olewine Donald A.
Published: December 2017

The increased urinary Na+ output induced by Diamox in water-loaded adrenalectomized rats was partially antagonized by the mineralocorticoid, desoxycorticosterone glucoside (DCG), the increased K+ excretion was augmented and urine volume was not affected. Intact rats subjected to the same treatment showed only a small, but significant, rise in K+ excretion. Under the same conditions, the glucocorticoid, hydrocortisone hemisuccinate (compound FH), significantly elevated Na+, K+ and H2O excretion in adrenalectomized rats receiving Diamox; intact rats showed an increase in Na+ and H2O excretion with no significant change in K+ output. Of particular interest is the finding that 2.5 mg compound FH alone increased H2O excretion in adrenalectomized rats to a slightly greater extent than Diamox alone with considerably less Na+ loss.
Influence of Morphine on Urinary Corticoid Excretion by Guinea Pigs Following Exposure to Cold and Administration of Pitressin
Authors: Sobel Harry , Schapiro Shawn , Marmorston Jessie
Published: December 2017

The influence of morphine administration on the excretion of urinary corticoids by the guinea pig has been investigated. Single doses of morphine greatly impaired the increased excretion of corticoids which was induced by exposure to cold but not that produced by Pitressin administration. In animals which were treated with multiple doses of morphine, the basal corticoid excretion was considerably reduced. However there appeared to be an increased responsiveness to cold as compared to guinea pigs which received single injections of morphine. Reactivity to Pitressin administration was now greatly diminished.
Comparisons of Some Fluctuations in Cosmic Radiation and in Organismic Activity During 1954, 1955 and 1956
Authors: Brown F. A. , Webb H. M. , Bennett M. F.
Published: December 2017

Average solar-day and lunar-day fluctuations in O2-consumption, or in spontaneous motor activity, were analyzed for eight species of animals and plants ranging from higher to lower forms for a total of 20 monthly periods in 1954 and 1955. These were compared with the concurrent fluctuations in cosmic radiation. Striking similarities were evident in every instance in either direct or mirror-image relationship. A further comparison, involving 18 single-day periods of metabolism and radiation in 1956, suggested that the average similarities seen are a consequence of a day-by-day response to some external fluctuating factor which pervades the so-called constant conditions and whose fluctuations are, either through a cause-effect or a parallel-induction relationship, correlated with the cosmic radiation.
Inhibition of Uric Acid Biosynthesis in Birds by o-Diazoacetyl-l-Serine (Azaserine) and 6-Diazo-5-Oxo-l-Norleucine (DON)
Authors: Krakoff Irwin H. , Karnofsky David A.
Published: December 2017

Uric acid, the principal end product of nitrogen metabolism in birds, was measured in the plasma and urine of birds during intravenous infusion of solutions of glucose, saline and ammonium acetate. Ammonium acetate infusions increased the content of uric acid in plasma and urine. Administration of o-diazoacetyl-l-serine (azaserine) and 6-diazo-5-oxo-l-norleucine (DON) at ld50 doses produced prompt and nearly complete inhibition of uric acid synthesis in chickens, pigeons and cormorants as demonstrated by a parallel fall in plasma and urine uric acid. This inhibition is due to a block in purine biosynthesis. The ability of birds to synthesize uric acid recovers within 12–24 hours in spite of delayed toxicity with 50% of birds dying in 3–5 days. There is a dissociation between the acute, transient effects of azaserine and DON on uric acid production and the slower evolution of a lethal effect.
Permeability of Smooth Muscle
Authors: Bozler Emil , Lavine Daniel
Published: December 2017

Penetration of sucrose into the muscle fibers of the frog's stomach is inferred from the observation that muscles swell in isosmotic sucrose solution and that sucrose space is consistently, on the average by 34%, larger than inulin space. In solutions of low electrolyte concentration water uptake and loss are strongly influenced by the presence of small amounts of Ca++ or Mg++. Thus muscles swell in isosmotic sugar solutions, but shrink after the addition of 2 mm CaCl2 or MgCl2. Also, swelling is several times smaller in 2 mm CaCl2 or MgCl2 than in pure water in spite of a smaller loss of electrolytes from the fibers. Swelling in sugar solutions and in diluted Ringer's solution is associated with a considerable loss of electrolytes from the fibers, which probably is partly responsible for the swelling. It is concluded that the charge of protein and intermolecular forces are important factors determining fiber volume. Although sucrose and fructose rapidly penetrate into the fibers, the spaces they occupy are much smaller than that of water. Most of the fiber volume, therefore, is not available as solvent for the sugars and may be ‘bound.’
Effect of Hypothermia on Tubular Transport Mechanisms
Authors: Segar William E.
Published: December 2017

Five mongrel dogs were cooled artificially to 20°C and then rewarmed to 37°C, while changes in the concentration of glucose, phosphorus, amino acid nitrogen, protein and creatinine in both plasma and urine as well as changes in urine flow were studied periodically. A decrease in serum amino acid nitrogen concentration occurred with cooling. The reverse was seen upon rewarming. Serum creatinine and protein levels were essentially unchanged. Urine flow increased with cooling and the U/P ratios of phosphorus, amino acid nitrogen and creatinine decreased. There was minimal increase in protein excretion while all of the filtered glucose appeared in the urine. The changes in urinary composition indicate that two transport mechanisms are involved in the reabsorption of amino acids and phosphorus from glomerular filtrate. Only one of these is affected by cooling. The mechanism responsible for glucose reabsorption is paralyzed by cold, while the effect of cold on protein reabsorption could not be quantitated by these studies.
Central Nystagmus. II. Relationship Between Central and Labyrinthine Nystagmus
Authors: Lachmann J. , Bergmann F. , Weinman J. , Welner A.
Published: December 2017

Rotation of a rabbit influences the ‘central’ nystagmus, provoked by electrical stimulation of a nystagmogenic area in the mesodiencephalon, in opposite sense during the acceleratory and deceleratory period, respectively. Nystagmic movements, produced by simultaneous central and labyrinthine stimulation, show enhancement, when they posses identical direction, and suppression, when their directions are opposite. The same rule applies to superposition of central and caloric nystagmus, the latter resulting from temperature changes near the tympanic membrane. When electrical stimulation is stopped, central nystagmus often increases its frequency for a short period.
Comparison of Tissue Respiration in Mice Exposed to Heat and Cold
Authors: Jasper R. L. , Denison M. E. , Zarrow M. X. , Hiestand W. A.
Published: December 2017

Oxygen uptake of liver, kidney and brain slices from cold-and heat-exposed adult, male mice was studied using the Warburg constant volume respirometer. In general, oxygen uptake showed certain similarities for both groups. The greatest oxygen increase from the control was observed after 72 hours of cold or heat exposure. For liver slices this was 21 and 6%, respectively; for kidney it was 23 and 27%; and for brain 33 and 31%, respectively. The lowest rate of oxygen uptake was seen after 48 hours of cold or heat exposure. For liver slices this was –27 and 6%; kidney, –7 and +14%; and for brain –10 and –2%, respectively. The mortality rate was increased in the heat-exposed more than in the cold-exposed animals. It is concluded that the response of oxygen uptake of these tissues from animals exposed to these divergent stresses (cold and heat) conforms to the pattern of the General-Adaptation-Syndrome.
Time Relations Among Metabolic and Morphologic 24-Hour Changes in Mouse Liver
Authors: Barnum Cyrus P. , Jardetzky Christine D. , Halberg Franz
Published: December 2017

Phospholipid and RNA metabolism in immature mouse liver, in different cell fractions obtained by centrifugation, are 24-hour periodic. Twenty-four-hour rhythms also characterize the metabolism of DNA and mitotic activity. The established 24-hour rhythm in liver glycogen content stands out clearly under standardized circumstances of observation. Some peaks and troughs of these rhythms are dissociated in time. To the extent that radiotracer methods used herein indicate formation of the metabolic variables studied, it may be inferred that, ordinarily, in immature mouse liver, the peak formation of both phospholipid and RNA consistently leads in phase 1) peak DNA formation by 6–8 hours; 2) peak glycogen content by about 12 hours; and 3) peak mitotic activity by about 16 hours. Phase-differences among the curves describe a sequential order among certain metabolic and morphologic events at the intracellular level, as well as the time relations of these events. Since the curves for nuclear and cytoplasmic RNAs are more congruous than those for nuclear RNA and DNA metabolic rather than localized intracellular factors probably underlie this periodicity.
Rate of Dephosphorylation of Adenosinetriphosphate and the Isotonic and Isometric Contraction of Glycerol-Treated Muscle
Authors: Bowen William J. , Martin Harold L.
Published: December 2017

A comparison of the rapidity of shortening in isotonic contraction and the development of tension in isometric contraction of glycerol-extracted muscle fibers was made. Increasing the concentration of magnesium causes shortening and tension to increase in a similar manner. These increases occur over a range of concentration of magnesium which has no effect on the adenosinetriphosphatase activity of the fiber-bundles. Increasing the concentration of calcium causes both isotonic and isometric contraction to decrease while the rate of splitting adenosinetriphosphate is increased. Increasing the concentration of potassium has no definite effect on contraction except above 0.2 m. Between 0.2 m and 0.3 m shortening increases while tension-development decreases. This dissimilarity is probably related to dissolution of the fibers.
Rate of Change in Sodium and Potassium Excretion After Injection of Aldosterone Into the Aorta and Renal Artery of the Dog
Authors: Ganong William F. , Mulrow Patrick J.
Published: December 2017

The rate of change in sodium and potassium excretion and reabsorption following the intra-arterial injection of single 2-, 5- or 10-µg doses of aldosterone was compared with the effect of similar doses injected directly into one renal artery, in nine adrenalectomized female mongrel dogs off replacement therapy for 48 hours. After a delay of 5–30 minutes, the hormone produced decreased sodium and increased potassium excretion, and a rise in sodium and a fall in potassium reabsorbtion associated with no consistent change in glomerular filtration rate. The magnitude of the response was greater with larger doses but the onset and rate of development of the changes were not changed. Direct injection into the renal artery produced changes which did not differ in their timing or magnitude from the effects of the same doses injected intra-arterially. The effect on the uninjected kidney was not significantly different from that on the injected side. PSP and Pitressin produced more profound effects on the injected side.
pH, Carbon Dioxide, Oxygen, Hemoglobin and Plasma Electrolytes in Blood of Pregnant Goats and Their Fetuses
Authors: Kaiser Irwin H. , Cummings John N.
Published: December 2017

The blood of 23 pregnant goats and their fetuses at 68 ± 2, 102 ± 2 and 139 ± 2 days of gestation was studied in regard to pH, blood gases, hemoglobin and electrolytes. The pH of maternal blood is higher and the pCO2 lower than that of the fetus. Oxygen saturation in the fetus drops toward term. Hemoglobin in the fetuses rises but does not reach adult levels at 139 days. Total determined electrolyte concentration is always higher in the maternal animal, although the difference becomes smaller as term approaches. Determined cations exceed determined anions in the maternal animals by about 3.5 mEq/l. At all stages of gestation studied there is a net deficit of determined anions in the fetus as compared with the mother, resulting largely from lower concentrations of protein and lactate. As protein rises toward term this deficit decreases but at 139 days still amounts to over 6 mEq/l. The net deficit of determined anions at 139 days in the fetus compared with its cation total is almost 9 mEq/l.
Experimental Renal Hypertension: Renin Content of Kidneys in Intact and Adrenalectomized Rats Given Cortexone
Authors: Gross F. , Lichtlen P.
Published: December 2017

The effects were investigated in rats of unilateral renal ischemia, adrenalectomy and varying doses of cortexone on the development of hypertension and on the content of pressor substances in the kidney. Adrenalectomy prevented the hypertension which follows unilateral clamping of the renal artery when a life maintaining dose of 0.1 mg cortexone acetate was injected daily. However, administration of 75 mg cortexone in the form of implants restored but did not enhance the characteristic hypertensive response to renal ischemia. The characteristic distribution of renal pressor material, being normal in the clamped and diminished in the contralateral kidney, was no longer observed after adrenalectomy when only small doses of cortexone were given but was still evident when excess cortexone was given. Overdosage with cortexone without clamping a renal artery led only to a moderate reduction of pressor material in both kidneys while in animals with unilateral renal ischemia the pressor material (renin?) in the contralateral kidney disappeared completely. Clamping the renal artery prevented the diminution of pressor material in the ipsilateral kidney which otherwise occurs under overdosage with cortexone in the normal animal.
Single Proximal Tubules of the Necturus Kidney. II. Effect of 2,4-Dinitrophenol and Ouabain on Water Reabsorption
Authors: Schatzmann Hans J. , Windhager Erich E. , Solomon A. K.
Published: December 2017

The effect of ouabain and 2,4-dinitrophenol on water reabsorption from the proximal tubule of the kidney of Necturus maculosus has been studied using the collection and stopped flow perfusion techniques previously described. The intravenous administration of ouabain in collection experiments results in a decrease in water reabsorption from 32.7% (normal controls) to 15.4%. In stopped flow perfusion experiments on control animals, water reabsorption after 20 minutes is 27.2%. When 2,4-dinitrophenol or ouabain is added to the perfusion fluids, values of 10.2% and 9.8%, respectively, are observed. The experimental findings demonstrate that water reabsorption in the proximal tubule is inhibited by these agents. The results are in agreement with the hypothesis of active reabsorption of sodium from the proximal tubule of the kidney of Necturus.
Specificity of the Sodium Chloride Appetite of Adrenalectomized Rats; Substitution of Lithium Chloride for Sodium Chloride
Authors: Fregly Melvin J.
Published: December 2017

A cafeteria or choice experiment was performed to determine the specificity of the NaCl appetite of adrenalectomized rats. In this experiment fluid intakes of male adrenalectomized rats were compared with those of male controls. All animals were allowed to choose freely between distilled water and a salt solution as drinking fluids. Nine different salt solutions were used with at least three separate concentrations of each salt being given. The salts used were: NaCl, LiCl, KCl, CaCl2, Na2SO4, Na citrate, Na oxalate, NaI and NaHCO3. Adrenalectomized rats showed a specific appetite for NaCl and gained weight only when this salt was given. Though greater volumes of Na2SO4, NaHCO3 and and Na citrate solutions were ingested than water, adrenalectomized rats lost weight on all of these. Normal rats failed to manifest an appetite for any of the salts offered. Particular attention was given to LiCl since this salt has been reported by others to stimulate chemoreceptors of the tongue of the anesthetized rat to produce electrical responses which are similar in amplitude to those initiated by the same concentration of NaCl. Both normal and adrenalectomized rats were given choice between NaCl solutions and water and later, between LiCl solutions and water. In equimolar concentrations, LiCl could not be substituted for NaCl; these two salts did not appear to ‘taste’ the same to either unanesthetized normal or adrenalectomized rats. Other experiments revealed that it was not possible to mask the ‘taste’ of LiCl in solution by mixing varying amounts of NaCl with it. However, a possibility exists that LiCl and NaCl taste the same to adrenalectomized rats and that LiCl is rejected because its toxic effects are manifested when small amounts are ingested.
Effects of Thermal Injury and of Skin Removal on Thyroid Function in the Rat
Authors: Reichlin Seymour , Lieberman Zelig H.
Published: December 2017

Thyroid I131 release rates have been measured in 6 rats before and after a 10–20% full thickness burn of the skin, and in 11 rats before and after resection of 10–20% of the dorsal skin surface. Thyroid function was inhibited for a variable period up to 30 hours after the burn in five of six animals. In contrast, flaying was followed in each of the 11 rats by increased thyroid function.
Varying Role of Extracellular Electrolytes in Metabolic Acidosis and Alkalosis
Authors: Tobin Richard B.
Published: December 2017

The responses of plasma and extracellular space to different types of acids and alkalis were studied in nephrectomized cats. Compensation for mineral acids can largely be accounted for by changes which are detectable in extracellular constituents. These changes are movement of Na+ and K+ into the extracellular space (ECS) and loss of HCO3– from the ECS. Organic acids which penetrate cells rapidly and may be expected to cause an intracellular and extracellular acidosis, produce negligible changes in extracellular content of Na and K. Alkalosis produced by NaOH or NaHCO3 was compensated for mainly by extracellular gain of bicarbonate and loss of Na. The response to NH4OH was unusual in that this alkaline solution caused an acidosis with movement of K into the ECS. The site of compensation for the various acids and alkalis was indicated by a comparison of the volume of agent infused with the change in volume of the ECS. The distribution of Na in these animals was not related as much to the concentration of Na in the ECS as it was to the pH produced by the solution infused. The response of the living organism to different types of acids and alkalis is variable and seems mainly related to the distribution of the material in the body.
Effect of Alterations of the Sodium Concentration of the Serum Upon the Content of Sodium in Bone
Authors: Winters Robert W. , Whitlock Robert T. , DeWalt Joseph L. , Welt Louis G.
Published: December 2017

The effects of alterations of the concentration of sodium in the serum upon the content of sodium in bone have been studied in rats in experiments of relatively short duration. Hyponatremia produced either by water loading in the presence of vasopressin or by peritoneal dialysis against glucose solutions was not associated with a significant fall in bone sodium. Hypernatremia produced by urea-loading and restriction of water intake was not associated with a significant rise in bone sodium. These experiments demonstrate that alterations in the concentration of sodium in the serum or in the volume of the extracellular fluid do not cause movements of bone sodium.
Temperature Response of the Rat to Action and Interaction of Chlorpromazine, Reserpine and Serotonin
Authors: Hoffman Roger A.
Published: December 2017

Reserpine was found to cause a prolonged increase in oxygen consumption while chlorpromazine and serotonin produced a comparable decline. Consequently, reserpine and chlorpromazine exhibited antagonistic interaction on the temperature response. Serotonin had little effect in modifying the temperature response to chlorpromazine, while prior treatment with serotonin appeared to delay the temperature decline seen with reserpine alone. Since the temperature declined following reserpine, in spite of an increased oxygen consumption, there was indicated both an increased heat production and a greatly increased heat loss. The data suggest that reserpine and chlorpromazine act by different mechanisms. Likewise, it is suggested that while reserpine and serotonin may act at similar sites, it is also apparent that different effector sites are differentially affected as well, at least insofar as thermoregulation is concerned.
Flow of lymph from the canine liver
Authors: Ritchie Horace D. , Grindlay John H. , Bollman Jesse L.
Published: December 2017

Observation of the hilar lymphatics from 100 canine livers seen at operation disclosed two drainage pathways: 1) a main hilar system, draining predominantly the right lobes and 2) an accessory hilar system, draining mainly the left lobe. In 94% of the animals all of the hilar lymph seemed to pass into one common efferent trunk which then discharged it into the cisterna chyli. Apparently, 69% of the animals had a lymph vessel large enough to permit cannulation for physiologic studies. From a study of five dogs in which the gallbladder was removed and the common bile duct ligated and in which there were fistulas of both the hilar lymph trunk and the thoracic duct, it was concluded that, normally, about 80% of the lymph leaving the canine liver probably travels by the hilar route and the remaining 20% by the hepatic venous lymph route. The mean flow of hilar lymph from the liver during biliary obstruction in 20 unanesthetized animals was 0.66 ml/kg body weight/hr., the standard error of the mean being ±0.07.
Prolongation of survival by parabiosis in strain 129 dystrophic mice
Authors: Hall C. E. , Hall O. , Nevis A. H.
Published: December 2017

Dystrophic mice were joined in parabiosis with normal partners of the same sex and strain. Their survival and the progress of the characteristic signs was compared with single controls, both normal and dystrophic. Comparisons between the size of certain organs were made. The usual brief survival of dystrophic mice was much prolonged by parabiosis, and the characteristic signs were often much reduced in severity. Adrenals were proportionately larger and kidneys smaller in single dystrophic mice as compared with normal controls. In contrast with normals the kidneys were also smaller in male dystrophic mice than in females. However parabiotic dystrophic mice had kidneys which were proportionately larger than in normal animals. The survival was often limited by the induction of cardiovascular disease, apparently as a consequence of parabiosis.
Enhancement of adrenocorticotrophic activity. III. Protein hydrolysates and amino acids
Authors: Cohen Herman , Megel Herbert , Kleinberg William
Published: December 2017

Using adrenal ascorbic acid depletion as a method of assay, it was observed that highly degraded gelatin enhanced ACTH activity to a greater extent than gelatin when subcutaneously administered. This led to the investigation of effect of other polypeptides and amino acids upon ACTH activity. Casein hydrolysate augmented ACTH activity at least fourfold over that of gelatin. Glutamic acid, lysine and pyrrolidone enhanced ACTH activity to the same degree as casein hydrolysate; whereas versene was as effective as gelatin. Casein hydrolysate was ineffective in augmenting FSH activity. The possible mechanism for the enhancement of ACTH by these various agents is discussed.
Metabolic alkalosis, a specific effect of adrenocortical hormones
Authors: Grollman Arthur P. , Gamble James L.
Published: December 2017

With appropriate balance experiments and skeletal muscle analyses, it was shown that: 1) Dogs placed on a potassium-restricted diet lost approximately 15% of their muscle cell potassium but did not develop alkalosis. 2) The administration of DCA, ACTH or cortisone to animals on a potassium-restricted diet evoked metabolic alkalosis which was sustained only as long as the hormones were administered. A prompt return to normal occurred despite continued potassium restriction. 3) Alkalosis induced by chloride withdrawal or by cortisone administration during complete sodium restriction was not associated with evidence of potassium loss. These findings indicate that the increase in the serum bicarbonate induced by the steroids is a relatively direct effect, one that cannot be dependably related in a reciprocal fashion to the associated losses of body potassium.
Peripheral blood epinephrine levels in dogs during intravenous infusion
Authors: Poole T. R. , Watts D. T.
Published: December 2017

Femoral arterial and venous blood epinephrine levels were followed in dogs during the infusion of l-epinephrine at rates of 1.25–10 µg (as the base)/kg/min. for periods of 37–197 minutes. The epinephrine concentration in arterial blood rose from control values of less than 1 µg/l., the lowest concentration that could be estimated, to levels of 8.5, 19, 75 and 201 µg/l. at infusion rates of 1.25, 2.5, 5 and 10 µg/kg/min., respectively. For these same infusion rates, the simultaneously determined venous blood levels were 7.8, 10, 27 and 70 µg/l., respectively. By extrapolation, these data show that at an infusion rate of 3.4 µg/kg/min., the lowest rate known to produce shock in dogs, the arterial blood level was 39 µg/l. This is approximately twice the maximum concentration of 20.6 µg/l. of endogenously released epinephrine observed during hemorrhagic shock in dogs.
Critical closing pressure and vasomotor tone in the hind leg and the kidney of the cat
Authors: Yamada S. I. , Åström A.
Published: December 2017

The isolated vascular beds of the hind leg and kidney in cats have been studied by analysis of the pressure-time curves obtained in the distal segment of the artery following occlusion of the arterial blood supply. Arterial flow after 2–3 minutes of occlusion becomes ‘zero,’ according to the criterion used (less than 0.0067 ml/min.), at an arteriovenous pressure difference of 7.8 ± 4.5 (S.D.) mm Hg in the leg and 7.0 ± 3.6 mm Hg in the kidney. Increased resistance to flow has been produced in both the leg and kidney by electrical stimulation of vasomotor nerves, intra-arterial injection of noradrenaline, lowering of the temperature of the local arterial blood and by increasing tissue pressure. The pressure-time curves show a slow but continuous drop and zero arterial flow, i.e. a ‘critical closure,’ is not obtained within the occlusion period. Decreased resistance to flow has been produced in the leg by denervation and by infusion of a ganglionic-blocking agent. Then, the pressure-time curves, as under normal conditions, show a final horizontal level of pressure (zero arterial flow) and the pressure at this point is lower than in the control tests. It is concluded that the level of arterial pressure at zero arterial flow (if obtained) is determined largely by the vasomotor tone and the tissue pressure, when the venous pressure is below 10 mm Hg. Considerable changes in resistance to flow occur with very small changes in the ‘minimum arteriovenous pressure difference’ required for flow. That ‘zero’ arterial flow is obtained only under special conditions would seem to limit the practicability of using critical closing pressure as a measure of vasomotor tone.
Regulatory mechanisms, brain activity and behavior during deep hibernation in the squirrel, Citellus beecheyi
Authors: Strumwasser Felix
Published: December 2017

During deep hibernation in the squirrel, Citellus beecheyi, focusing of attention, discrimination, attempts to localize sound stimuli in space, vocalization and complex motor coordinations are all possible at brain temperatures of 6.1°C and compatible with the 90% reduction of amplitude of general brain wave activity present at these temperatures. Brain temperatures during deep hibernation are maintained within ±0.05°C at 2°–3°C above environmental temperature, while skin temperature is fluctuating ten to twenty times as much. Other significant details of cardiovascular, temperature and muscle tone regulation during this state are analyzed. Cortical and subcortical neuronal activity is present in deep hibernation and can have the appearance of that of an alert squirrel brain at merely reduced amplitude. Quiet areas are shown not to be merely temperature depressed in excitability. It is tentatively suggested that the deeply hibernating animal may be extremely dependent on maintaining the spontaneous cerebral electrical activity normally present and any drug which completely eliminates it for too long a time, by preventing the dynamic patterns of activity normally present from being reorganized, allows the break of the final link between animal and environment. This is considered responsible for the ‘death’ of the animal rather than any failure of the supply systems.