bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE BEHAVIOUR OF PLATELETS IN VIVO
Authors: Silver M. D. , Stehbens W. E. 
Published: December 2014

Observations have been made on platelet behaviour in non‐inflamed and growing blood vessels in the rabbit ear chamber. Platelets showed little tendency to aggregate or to adhere to endothelium. Most commonly a few adhered to leucocytes which were attached to or rolled along the endothelium.Platelets adhered to leucocytes in larger numbers and aggregated to form microthrombi and emboli following mild trauma and intravascular injection of adenosine diphosphate, Pelikan ink and methyl cellulose. Following intravascular administration of thrombin and bacterial lipopolysaccharides (S. typhosa and E. coli) platelet aggregation was observed and later hyaline thrombi. In addition, aggregation of erythrocytes occurred with methyl cellulose.
THE GOLGI APPARATUS IN SMALL LYMPHOCYTES AND IN TRANSFORMED BLAST CELLS
Authors: Coulson A. S. 
Published: December 2014

The Golgi apparatus can be demonstrated by incubating cells in a medium containing lead nitrate and either thiamine pyrophosphate or a nucleoside diphosphate. Enzyme activity at the Golgi membranes hydrolyses the thiamine pyrophosphate or nucleoside diphosphate and a precipitate of lead phosphate is formed. By converting this precipitate into lead sulphide the Golgi apparatus can be visualized microscopically.The enzyme activity in freshly separated human small lymphocytes is barely detectable.After tissue culture for 80‐90 hr. with an antigenic stimulus some of the small lymphocytes transform into blast cells. The transformed blast cells contain a well‐developed Golgi apparatus which is basically a figure‐of‐eight shape. Blast cells in mitosis do not contain a Golgi apparatus.This evidence suggests that the transformed blast cell is manufacturing protein, possibly antibody.
THE ACTION OF ANTICHOLINESTERASES ON THE RESPONSE OF THE PACE‐MAKER, THE CONDUCTING SYSTEM AND THE VENTRICULAR MUSCULATURE OF PERFUSED FROG HEARTS TO ACETYLCHOLINE
Authors: Boyd I. A. , Pathak C. L. 
Published: December 2014

Concentration‐response curves were obtained for the action of acetylcholine (ACh) on frog hearts perfused under controlled dynamic conditions. The cardiac output, frequency of contractions, and arterial pressure developed by the heart were continuously recorded electronically.The minimum concentration of ACh that affected pace‐maker frequency and ventricular tone was about the same, and was unaffected by the presence of anticholinesterases. The action of ACh on pace‐maker frequency was potentiated by anticholinesterases, the degree of potentiation increasing with concentration of ACh. There was a limit to the degree of inhibition of ventricular tone attainable with ACh, this limit varying from 40 to 100 per cent in different hearts. Inhibition of ventricular tone by ACh was often unaltered, or even reduced, by anticholinesterases. The sensitivity of the conducting system to ACh varied greatly from heart to heart, and was independent of the sensitivity of either pace‐maker or ventricular muscle. The concentration of ACh required to arrest the heart was always less in the presence of anticholinesterases.The results are explained in terms of differences in the amount and type of cholinesterase present in the component tissues of the heart, and by competition between the direct atropine‐like action of some anticholinesterases on muscle and their action in inhibiting cholinesterase.
EFFECT OF HYPOPHYSECTOMY OR TREATMENT WITH THYROXINE OR TESTOSTERONE ON SECRETORY RESPONSES AND RESPIRATORY ENZYMES OF THE SUBMAXILLARY GLAND OF THE RAT
Authors: Ohlin P. 
Published: December 2014

The effect of hypophysectomy or of treatment with thyroxine or testosterone on the function of the submaxillary gland of rats was studied. (1) The dry weight of the submaxillary gland decreased by 46 per cent after hypophysectomy. The gland weight increased by 14 per cent after thyroxine and by 29 per cent after testosterone. (2) The maximal secretory response to pilocarpine was reduced after hypophysectomy. After hormonal treatment the maximal secretory response was increased when expressed per gland. It was also increased when calculated per unit weight after thyroxine, but not after testosterone. (3) The activity of succinic dehydrogenase, cytochrome oxidase and fumarase was not significantly changed after hormonal treatment when expressed per unit weight.The results are discussed and related to known morphological changes of the submaxillary gland of rats after hypophysectomy or after treatment with thyroxine or testosterone.
INTERACTION OF ADRENERGIC ALPHA AND BETA‐RECEPTOR BLOCKING AGENTS ON THE BLOOD PRESSURE RESPONSE TO ADRENALINE AND NORADRENALINE
Authors: Sharma P. L. 
Published: December 2014

The interaction of adrenergic alpha and beta‐receptor blocking agents on the blood pressure response to adrenaline and noradrenaline was studied in anaestheitzed dogs.Dibenzyline completely blocked the pressor response to noradrenaline, and converted the pressor response to adrenaline into a depressor one. Propranolol partially restored the pressor responses to both noradrenaline and adrenaline. The increase in heart rate produced by catecholamines was completely blocked by propranolol.In another group of dogs, propranolol was administered before dibenzyline. Propranolol potentiated the pressor responses to both adrenaline and noradrenaline. The potentiation was more marked with adrenaline than noradrenaline. The increase in heart rate produced by these catecholamines was completely blocked by propranolol. Dibenzyline reduced but did not abolish the pressor responses to both adrenaline and noradrenaline.Propranolol partially antagonizes the action of dibenzyline. This antagonsim appears to be independent of the myocardial actions of adrenaline and noradrenaline.
THE EFFECT ON MUSCLE GLYCOGEN OF SHOCK DUE TO SPINAL CORD DESTRUCTION, AND OF HAEMORRHAGIC SHOCK WITH PERIPHERAL DENERVATION
Authors: van Gool J. , Reerink E. 
Published: December 2014

In rats with shock due to spinal cord destruction (pithed rats) and severe terminal hypoglycaemia muscle glycogen remains normal, whereas it falls in shock due to other causes. To explain this difference the role of denervation on muscle glycogen was investigated.In rats with destruction of the lower part of the spinal cord, the denervated hindlimbs showed a higher muscle glycogen concentration than the normally innervated forelimbs, in spite of severe shock. In other experiments is was found that in haemorrhagic shock one‐sided proximal interruption of the femoral nerve resulted in a higher glycogen concentration in the rectus femoris than on the other sham‐operated side. However, the same differences were found also in the gastrocnemius, whose motor nerve fibres were intact. Blockade with phenoxybenzamine prior to haemorrhagic shock abolished this difference between the denervated and intact limb completely. It is concluded that a section of the femoral nerve interrupts accompanying sympathetic adrenergic fibres to the hindlimb, thereby preventing vasoconstriction and reducing tissue hypoxia during haemorrhagic shock. The normal muscle glycogen concentration during severe spinal shock must be explained by a failure of reflexogenic hyperactivity of the sympathetic nervous vasomotor system.In studies on the effects of peripheral denervation, the possible role of interruption of accompanying autonomic nervous fibres is often neglected.
EFFECTS OF VASOPRESSIN UPON THE COMPOSITION OF RAT'S KIDNEY
Authors: Abedin Zain Ul 
Published: December 2014

The composition of renal medulla and cortex was studied in rats during water diuresis interrupted by lysine‐8‐vasopressin (ADH), given as a single intravenous injection or by continuous intravenous infusion, in an attempt to mimic the effect of hydropenia.Continuous infusion of 60 µu./100 g./min. ADH for 2½ hr. (9 mu. in all) raised the osmolality of the medulla and urine to the levels found after 24 hr. of hydropenia, but these values remained lower than values reported after prolonged hydropenia. Infusion of 30 µu./100 g./min. ADH (4·5 mu. in all) was only slightly less effective. 10 mu./100 g. body weight of ADH given as a single intravenous injection increased the osmolality of medulla less than did continuous infusion of this hormone.Accumulation of sodium in deeper medulla and at the level of thick portion of ascending limb of loop of Henle suggests that ADH may promote transport of sodium from collecting ducts and the thick ascending limb of loop of Henle or the other structures present at these levels. The amount of potassium in the deeper medulla diminished after ADH treatment. Increased amount of water at the level of the ascending limb suggests the possibility of short‐circuiting of water at this level; this would partly account for the low water content found in the deeper medulla. Accumulation of urea and ammonium in the medulla is also reported.
THE EFFECTS OF VOLUNTARILY CONTROLLED ALVEOLAR HYPERVENTILATION ON CARBON DIOXIDE EXCRETION
Authors: Stoddart J. C. 
Published: December 2014

Four subjects hyperventilated at three carefully controlled alveolar ventilation levels. It was found that carbon dioxide excretion and the rate of change of alveolar carbon dioxide tension were related to the alveolar ventilation.Three exponential components were recognized in the carbon dioxide excretion curves and their time constants determined. These were related to the body stores from which carbon dioxide was removed.The slope of the whole body carbon dioxide dissociation curve was found to be related to the alveolar ventilation level and ranged from 1·17–2·03 ml./mm. Hg./min,
STUDIES UPON THE RELATIONSHIP BETWEEN BARORECEPTOR AND SYMPATHETIC ACTIVITY
Authors: Green J. H. , Heffron P. F. 
Published: December 2014

Simultaneous recordings of sympathetic activity in the right inferior cardiac nerve, and of baroreceptor activity in the common carotid baroreceptor nerve were made in cats with an isolated common carotid artery and sinus area.The effect of the change from non‐pulsatile to pulsatile sinus pressure was to impose a rhythm synchronous with the pump upon sympathetic activity. The changes in amplitude of sympathetic activity were investigated.The inhibition of sympathetic activity by carotid traction was used to identify sympathetic fibres.The baroreceptor‐sympathetic reflex delay was of the order of 200 m/sec. thus providing a beat to beat control of cardiac activity.
EFFECTS OF SELECTIVE MYOCARDIAL INACTIVATION ON LEFT VENTRICULAR FUNCTION DURING THE ISOVOLUMETRIC PHASE OF SYSTOLE
Authors: Taylor D. E. M. , Wade J. D. , Shishodia M. S. , Hider C. F. 
Published: December 2014

The pressure changes in the left ventricle during the isovolumetric phase of systole have been studied in the dog before and three months after selective inactivation of between 5 per cent and 8 per cent of left ventricular myocardium. In fourteen animals the anterior papillary muscle was inactivated and in thirteen animals an equivalent mass of myocardium in the antero‐lateral wall of the left ventricle was inactivated. In both series left ventricular systolic pressure and mean cycle length were not significantly changed by the procedures. In the animals with lateral myocardial inactivation the mean left ventricular end diastolic pressure (LVEDP) was raised from 4·4 mm. Hg to 6·3 mm. Hg. The maximum rate of isovolumetric pressure rise was not significantly changed; it was 2530 mm. Hg/sec. initially and 2580 mm. Hg/sec. 3 months after inactivation. The mean time to reach the maximum rate of pressure rise was also unaffected, being 31 m/sec. initially and 30 m/sec. 3 months after inactivation. The first derivative of left ventricular pressure with respect to time was plotted; it was unchanged up to the peak rate of pressure rise (dP/dt max), apart from the higher LVEDP, but thereafter the curve showed a more rapid falling off. In the animals with papillary muscle damage the mean LVEDP was increased from 4·6 mm. Hg to 5·9 mm. Hg, (dP/dt) max fell from 2630 mm. Hg/sec. to 2020 mm. Hg/sec., and t(dP/dt)max lengthened from 29 m/sec. to 38 m/sec. All these changes were statistically significant. In the first derivative of pressure with respect to time the changes were seen as a fall in the peak value and a shift of the peak to the right. In six of the fourteen animals with papillary muscle damage mitral valve incompetence was produced. The changes in the isovolumetric portion of the pressure curve occurred whether or not mitral valve incompetence was present, but were accentuated when it was.The contraction of the ventricle is a sequence of the contractions of its parts; the present results demonstrate that papillary muscle contraction is important early in thie seqcuence, at the start of the isovolumetric phase of systole.
FIBRINOLYTIC ACTIVITY IN ANIMALS OF DIFFERENT SPECIES
Authors: Irfan M. 
Published: December 2014

Studies have been made on the activation of animal plasminogen in vitro and in vivo. Whole blood lysis times and euglobulin lysis times were determined for animals of different species. Dilution enhanced spontaneous lysis time of dog blood but not of cattle, horse, sheep and rabbit blood.The dog blood contains proactivator and is activated by streptokinase. The initial streptokinase dose has been determined for dog blood in vivo. The blood of cattle, horses, sheep and rabbits was activated by urokinase which does not seem to require the presence of proactivator.A tissue activator was present in the lymph nodes, kidneys, spleen and heart muscle but not in the liver of rabbits. Autographs from fresh frozen sections confirmed areas of fibrinolysis around the blood vessels, especially in the region of capillaries and small veins.Two dogs on chlorpropamide showed a temporary increase in fibrinolytic activity and later developed resistance to the drug. Chlorpropamide had no fibrinolytic effect in rabbits.
ACTION OF SOME THIAMINE ANTAGONISTS ON FROG TASTE RECEPTORS
Authors: Perri V. , Rapuzzi G. , Sacchi O. 
Published: December 2014

The influence of some thiamine antagonists (pyrithiamine and oxythiamine) on the response of frog taste receptors to chemical stimulation was studied. Isolated frog tongue preparations were perfused through the lingual artery with Tyrode solutions containing different amounts of pyrithiamine or oxythiamine. Pyrithiamine strongly depresses tongue receptor response to chemical stimulation. Its action however can be almost completely prevented by equimolar amounts of thiamine. Conversely oxythiamine does not affect taste receptor function even when perfused in elevated concentrations.These results are interpreted as a proof that thiamine is essential in frog's taste receptor activation. The lack of any action of oxythiamine can be explained by considering that this substance acts as cocarboxylase antagonist only when phosphorylated and that it cannot be easily phosphorylated in vivo. Pyrithiamine, on the other side, is known to interfere with the phosphorylation of thiamine. On this basis it is suggested that thiamine may be involved in its phosphorylated form in taste receptor function.
ON THE PRESENCE OF GLUTAMINASE IN MUSCLE
Authors: Ottaway J. H. 
Published: December 2014

The glutaminase activity of rat cardiac and skeletal muscle has been investigated, and compared with that of rat kidney. Vmax per g. of protein was 42 µmole/hr for heart muscle homogenates and 478 µmole/hr for kidney homogenates. Glutaminase activity was not detectable in about 50 per cent of the skeletal muscle homogenates; in the other 50 per cent the mean activity was about 30 µmole/g. protein/hr. The apparent Km of the enzyme in all 3 tissues was approximately 4 mM.Bovine growth hormone injected into rats for 5 days did not alter the level of glutaminase activity in kidney or cardiac muscle, but significantly increased the percentage of skeletal muscle homogenates in which glutaminase was detectable.
THE MECHANISM OF FAT ABSORPTION IN THE BILE FISTULA RAT
Authors: Morgan R. G. H. , Borgström B. 
Published: December 2014

Fat absorption was studied in normal and bile fistula rats using test meals of corn oil containing radioactively labelled triolein. Two types of test meal were used, which would produce differently labelled monoglyceride and fatty acid under the action of pancreatic lipase.Triolein containing 3H labelled oleic acid in the 1 and 3 positions and 14C labelled oleic acid in the 2 position was fed to normal and bile fistula rats with and without lymph fistulae. Short term pancreatic lipolysis of this triolein produced 3H labelled fatty acid and 14C labelled 2‐monoolein. Fat balance studies, Cori type experiments and the recovery of label in the lymph showed that in bile fistula rats 3H was absorbed in excess of 14C during the first few hr after feeding. In contrast, in lymph fistula rats with a normal bile flow 14C was absorbed in excess of 3H except in the earliest sample. These results indicate that after digestion triglyceride is absorbed mainly as fatty acid in the bile fistula rat, but as a mixture of fatty acid and monoglyceride in the normal animal. Analysis of lymph lipids confirmed that the mechanism of absorption is different in the bile fistula and normal animals.A mixture of triolein labelled with 3H in the glycerol moiety and triolein labelled with 14C in the fatty acid moieties was also used as a marker in corn oil test meals fed to lymph fistula rats with and without bile diversion. In bile fistula rats the early lymph samples contained more 3H than 14C, but from 6 hr onward 14C predominated, and overall more 14C than 3H was recovered in the lymph. It seems probable that the early high recovery of 3H was due to the incorporation of free glycerol into lymph lipids in these animals. The overall recovery of 14C in excess of 3H is consistent with the concept that triglyceride is absorbed chiefly as fatty acid in the absence of bile. In animals with a normal bile flow 14C was absorbed in excess of 3H throughout the recovery period.It is concluded that the mechanism of fat absorption in the bile fistula rat is not the same as it is in the presence of bile. Possibly fatty acid may be absorbed as soaps in the absence of bile, but no mechanism for the absorption of intact monoglyceride by these animals can be suggested.
PLASMA CORTICOSTERONE IN THE RAT IN RELATION TO TRAUMA AND ENVIRONMENTAL TEMPERATURE
Authors: Tilstone W. J. , Roach P. J. 
Published: December 2014

Male Wistar rats show a marked rise in plasma corticosterone 1 hr after fracture of a femur under halothane‐oxygen anaesthesia when they are housed at 200° C. or at 30° C. Anaesthesia alone produces a less marked response. No elevation is seen 6 hr after fracture or anaesthesia alone at 200° C.The animals were handled frequently and blood taken from unhandled animals gave results for plasma corticosterone about three times higher than handled controls.Controls, and animals only anaesthetized, had lower plasma corticosterone levels at 30° C. than at 200° C.; but there was no such difference between the animals undergoing fracture at 200° C. and those at 300° C.
INTERRELATION OF RESPONSES DURING PROGRESSIVE EXERCISE IN TRAINED AND UNTRAINED SUBJECTS
Authors: Edwards R. H. T. , Jones N. L. , Oppenheimer E. A. , Hughes R. L. , Knill‐Jones R. P. 
Published: December 2014

In twelve cyclists (‘trained’ group) and twelve sedentary subjects (‘untrained’ group) the cardiovascular, pulmonary and metabolic responses to submaximal cycle ergometer exercise have been investigated. Lower values for ventilation (VE), heart, rate (HR), cardiac output (VQ), respiratory exchange ratio (R) and blood lactate (La) were found in the trained group. When related to oxygen intake as percentage of predicted maximum the responses of VE, HR and Q were similar in the two groups but values for La remained lower in the trained subjects. It was concluded that a more rapid and more efficient distribution of cardiac output occurred in the trained group.Five ‘trained’ and four ‘untrained’ subjects were studied during maximal work. Similar values for Q, HR and La were found in both groups; VE was higher and constituted a significantly higher proportion of the ventilatory capacity (sustained M.V.V.) in the trained compared with the untrained group (81 per cent and 66 per cent respectively). In both groups the rate at which ventilation increased as maximal loads were approached may have led to a ventilatory limitation to further work.
STUDIES ON THE IN VITRO FORMATION OF MONOIODOTYROSINE BY SOLUBLE SUPERNATANT OF PIGEON THYROID GLAND
Authors: Bhattacharya Samir , Datta Asoke G. 
Published: December 2014

A soluble supernatant preparation of pigeon thyroid gland can catalyse the iodination of tyrosine to monoiodotyrosine in vitro. The enzyme needs a hydrogen peroxide generative system such as glucose and glucose oxidase or Cu2+ for its activity. The optimum concentration of Cu2+ was found to be 1·33 x 10−3 M. Direct and slow addition of hydrogen peroxide cannot be substituted for Cu2+.Antithyroid agents like thiourea and thiouracil are found to be more potent inhibitors of avian enzyme than of mammalian enzyme. Ascorbic acid inhibits the enzyme but stimulates remarkably when a dialysed enzyme is used instead of an undialysed one.
INTRACELLULAR pH IN MATURE AND IMMATURE RABBIT RED CELLS
Authors: Calvey T. N. 
Published: December 2014

The intracellular pH of rabbit red cells was determined from the distribution of (2‐14C) DMO. Evidence is presented that the method provides a valid estimate of intracellular pH. In phosphate buffer at pH 7·40, the mean intracellular pH of the rabbit erythrocyte was 7·27. There was a close correspondence between the distribution ratios for hydrogen and chloride ions in normal rabbit blood. Values for intracellular pH, based on forty experiments in normal animals, were consistent with recent measurements of the membrane potential of mammalian red cells.The intracellular pH of the reticulocyte was deduced from the effect of acetylphenylhydrazide on the internal pH of rabbit red cells. At an external pH of 7·40, mean reticulocyte pH (7·32) was 0·06 pH units higher than mean erythrocyte pH (7·26).In preparations of reticulocytes, the distribution ratio for chloride ions was lower than the corresponding ratio for hydrogen ions. It is suggested that the presence in reticulocytes of small numbers of relatively alkaline mitochondria may be responsible for this phenomenon.
SOME PHYSIOLOGICAL ASPECTS OF ALPHA AMINO NITROGEN METABOLISM IN THE UTERUS OF THE PREGNANT AND NON‐PREGNANT EWE
Authors: Curet Luis B. , Crenshaw Carl , Mann Leon , Abrams R. H. , Barron D. H. 
Published: December 2014

Arterial and uterine venous concentrations of alpha amino nitrogen and uterine blood flow were repeatedly measured in twelve non‐pregnant and ten pregnant Dorset ewes.The arterial levels and uterine arteriovenous differences of alpha amino nitrogen were low early in gestation and gradually increased to approach non‐pregnant values towards the end of gestation. The uterine uptake of alpha amino nitrogen per kilogramme of uterine tissue behaved in a similar way but remained lower than the uptake per kilogramme of tissue by the non‐pregnant uterus.The data suggest that the removal of amino acids by the uterus is independent of the levels in the blood reaching the organ.