bluuebunny/crossref_metadata_2025_split huggingface dataset:
QUANTITATION OF FUNCTIONAL DIFFERENCES BETWEEN THE TWO SEGMENTS OF THE RAT PROXIMAL TUBULE IN THE HANDLING OF CHLORPHENOL RED AND HIPPURAN‐131I
Authors: Sottiurai Vikrom , Longley James B. 
Published: December 2014

The work reported in this paper attempts to associate several functions known to occur in the renal proximal tubule with either the convoluted or straight segment of this tubule, and from observations made on a zonal basis to offer conclusions concerning the specific functions of these segments. Measurements were made of chlorphenol red and hippuran‐131I in kidneys of diuretic rats which had one ureter ligated to create stop‐flow conditions. Autoradiographs were also obtained from the hippuran‐131I study.The results show that chlorphenol red and hippuran‐131I accumulate in the cortex in kidneys after ligation of the ureter and in the outer stripe of the outer zone of medulla in free urine flow kidneys.The measurements made in renal tissue when compared with the plasma and urine levels of chlorphenol red and hippuran‐131I obtained during the experiments, indicate that these substances are actively secreted at both the vascular and luminal margins of the epithelial cell of the convoluted segment and passively reabsorbed by the epithelial cells of the straight segment.
MECHANISM OF ANTITREMORINE‐ACTIVITY OF ADRENERGIC BETA‐RECEPTOR ANTAGONISTS IN THE RAT
Authors: Sharma P. L. 
Published: December 2014

The effect of dl‐propranolol, d‐propranolol, dl‐INPEA and d‐INPEA on tremor induced by tremorine (1,4‐dipyrrolidino‐2‐butyne dihydrochloride) was studied in the rat by administration both before and after the tremorine. Hyoscine was used as the standard drug for comparison.Both dl‐propranolol and dl‐INPEA reduced the intensity of tremors. On a weight to weight basis dl‐propranolol was more potent than hyoscine, while dl‐INPEA was less potent than hyoscine. Both d‐propranolol and d‐INPEA had no appreciable effect on the tremorine‐tremor. The anti‐tremor activity is thus related to the potency of these drugs as beta‐receptor antagonists.
THE METABOLISM OF FRUCTOSE AND GLUCOSE BY THE SHEEP FOETUS: STUDIES ON THE ISOLATED PERFUSED PREPARATION WITH RADIOACTIVELY LABELLED SUGARS
Authors: Alexander D. Pauline , Britton H. G. , Nixon D. A. 
Published: December 2014

1. The metabolism of fructose and glucose in the perfused isolated sheep foetus was studied using 14C‐labelled sugars.2. At 105–135 days of conceptual age the foetus metabolized fructose at a rate equivalent to only a small fraction of the oxygen consumed. Plasma fructose showed little or no turnover, indicating a negligible endogenous formation of the sugar.3. A substantial part of the fructose appeared as CO2; about 3 per cent of the total CO2 excretion could come from this sugar. This proportion was inversely related to the plasma glucose concentration and was markedly depressed when glucosewas administered.4. [U‐14C] glucose rapidly disappeared from the circulation and much of the label appeared in the CO2 in the experimental period. The rapid turnover was compatible with glucose as the major foetal metabolite.5. Glycogen showed only trace labelling in liver, heart muscle and skeletal muscle after giving the [U‐14C] sugars. Indications were obtained that cardiac glycogen can be depleted by both hypoglycaemia and hypoxia.6. The urine contained only small amounts of both sugars.7. Foetal blood cells were shown to take up fructose in the absence of glucose, a fact which could account for a considerable fraction of its disappearance from the blood.8. It is concluded that the above observations are compatible with fructose being a reserve for use when little glucose is available; the amount utilized is, however, always small. It may be that fructose is used only by tissue lacking stores of glycogen.
RENAL EXCRETION OF ACID IN CALVES FED EITHER ROUGHAGE OR CONCENTRATE DIETS
Authors: Scott D. , Whitelaw F. G. , Kay Moira 
Published: December 2014

Calves fed a roughage diet (50 per cent hay + other components) excreted an alkaline urine rich in bicarbonate but poor in phosphorus. Infusion of HCl into the rumen led to a fall in urine pH, to a decrease in bicarbonate excretion and to the excretion of acid in the urine. Between 16–25 per cent of this acid was excreted as acid phosphate (H2PO4-) and the remaining 75–84 per cent as ammonium ions.In contrast, when the calves were fed a concentrate diet (85 per cent barley + other components) the urine was acid and contained appreciable amounts of phosphorus and ammonium ions. Infusion of HCl into the rumen produced a further increase in acid excretion, practically all of which appeared in the urine as ammonium ions.Excretion of calcium in the urine increased during infusion of HCl and was correlated with urine pH.There were few changes in faecal mineral excretion during acid infusion but less sodium and potassium were excreted in the faeces when the concentrate diet was fed compared to when the roughage diet was fed.
METABOLIC CHANGES INDUCED BY TISSUE INJURY: IN VITRO STUDIES WITH RAT LIVER SLICES
Authors: Nitzan M. , Groffman H. 
Published: December 2014

To study the metabolic response to tissue injury, in vitro studies with rat liver slices have been conducted. Liver slices, from fasted rats which had undergone standard midline laparotomy 24 hr before, showed a 14‐fold increase in the incorporation of acetate‐2‐14C into cholesterol, with no change in the conversion of the acetate to other lipid fractions or 14CO2.The fate of L‐alanine‐14C has also been determined. The same physical injury brought about a 7‐fold increase in the production of cholesterol‐14C, a 66 per cent increase in the incorporation of the alanine into liver proteins, and a 35 per cent increase in the evolution of lactic acid‐14C. The radioactivity of other lipid classes, 14CO2, glucose or glycogen was not significantly different from the corresponding control values.These data are compatible with a striking and specific stimulating action of surgical injury upon cholesterogenesis. In addition, though the known effect of physical injury in the peripheral tissues is excessive breakdown of proteins, the results suggest enhanced hepatic protein synthesis after injury.
THE EFFECT OF EXERCISE UPON ACETOACETATE METABOLISM IN ATHLETES AND NON‐ATHLETES
Authors: Johnson Ralph H. , Walton John L. 
Published: December 2014

Thirteen male subjects at rest took sodium acetoacetate (200 ml., 0·4 M) by mouth and the subsequent changes in blood ketone bodies (acetoacetate plus 3‐hydroxybutyrate), glucose, glycerol and free fatty acids were measured at intervals. Five of the subjects were in a state of athletic training and the others were not. Three of the trained subjects and six of the untrained were then given the same dose of acetoacetate during and again after a 1·5 hr run, and similar measurements made and compared with those during a run without giving acetoacetate.At rest, no difference appeared between the trained and the untrained; but after running, only the untrained showed significant ketosis and a decreased tolerance to acetotacetate. It is concluded that acetoacetate utilisation rises during exercise, and production is well matched to utilization in the athletically trained subject, but is excessive during and after exercise in the untrained subject.
THE EFFECT OF COLD EXPOSURE ON PLASMA LIPIDS OF THE NEW‐BORN AND ADULT OX
Authors: Thompson G. E. , Clough D. P. 
Published: December 2014

The plasma total free fatty acid (FFA) concentration of ten calves at birth was low, averaging 4·3 mg/100 ml. Five of these animals were exposed to an environment of +25°C immediately after birth, and their plasma FFA concentration increased significantly by 7·5 mg/100 ml. (P 〈 0·05) after the first hour of life. The other five animals were exposed to an environment of +5°C, and they also had a significant increase in plasma FFA concentration after the first hour of life, averaging 25·6 mg/100 ml. (P 〈 0·001). The increase in the group exposed to +5°C was significantly greater than the increase in the group exposed to +25°C (P 〈 0·001). No other plasma lipid fraction altered with change in environmental temperature.Five adult steers exposed to a thermoneutral environment (+15°C) had a mean plasma total FFA concentration of 10·7 mg/100 ml. at the end of 2 hr exposure. In a cold environment (−20°C) this was increased by 8·4 mg/100 ml. (P 〈 0·01) but no other plasma lipid fraction was altered.In one adult animal the adrenal glands were denervated and this had no effect on the increase of plasma FFA in the cold. The other 4 adults were injected with bethanidine, a sympathetic nerve blocking agent, and this reversed the change of plasma FFA concentration at −20°C and also reduced the increase in oxygen consumption which normally occurred at this environmental temperature.It is concluded from these experiments that the plasma FFA concentration of new‐born and adult oxen increases when they are exposed to a cold environment, and in the adult this increase is mediated through the sympathetic nervous system.
THE INVOLVEMENT OF MAST CELLS IN VASODILATATION DUE TO AXON REFLEXES IN INJURED SKIN
Authors: Kiernan J. A. 
Published: December 2014

Immediately subjacent to a scratch damaging the epidermis of the external ear of the albino rat, all the dermal mast cells are degranulated. The proportion of degranulating mast cells is increased from about 43% to about 56% in areas of vasodilatation due to axon reflexes in the skin surrounding such a scratch. A similar degree of degranulation follows antidromic stimulation of the common trunk of the great auricular and lesser occipital nerves. It is shown that the degranulation of mast cells, like the vasodilatation, is mediated by the somatic sensory axons supplying the skin.A theory is advanced in which it is proposed that histamine, released from degranulated mast cells at the site of an injury, stimulates sensory nerve endings initiating an axon reflex. A transmitter substance, possibly adenosine triphosphate, is released from other terminations of the same neuron and causes degranulation of mast cells. Proteolytic enzymes released from these mast cells act upon a substrate present in the extracellular fluid to form bradykinin, which dilates nearby arterioles.
EXCRETION OF PHOSPHORUS AND ACID IN THE URINE OF SHEEP AND CALVES FED EITHER ROUGHAGE OR CONCENTRATE DIETS
Authors: Scott D. 
Published: December 2014

Sheep and calves fed a roughage diet (53% straw + other components) excreted an alkaline urine poor in phosphate whereas when they were fed concentrate diets (80% barley + other components) the urine was acid and contained large amounts of phosphate of which a high proportion were present as titratable H2PO‐4. These differences in phosphorus excretion were not related to differences in phosphorus intake nor did they appear to be directly related to acid excretion. Over a wide range in the amount of phosphate filtered at the glomerulus the amount reabsorbed by the renal tubule was consistently less in animals fed the concentrate diets. These differences in tubular reabsorption appeared to be related to differences between diets in the amounts of phosphorus absorbed from the gut but there were no differences between diets in the level of parathyroid hormone in blood.Both sheep and calves fed a concentrate diet composed of barley and fish meal excreted considerably more acid in the urine than when fed a similar diet in which soya bean meal was substituted as the source of protein. The reasons for this difference in acid excretion are not yet clear.
PLACENTAL TRANSFER OF IRON IN THE GUINEA PIG
Authors: Wong C. T. , Morgan E. H. 
Published: December 2014

The uptake of transferrin and iron by the placenta and iron transfer to the fetuses were studied in the guinea pig using radioiodine labelled guinea pig transferrin and albumin and 59Fe. The amount of labelled transferrin bound by the placenta increased during the first 30 min after injection, then reached steady levels which were maintained for the next 60 min. No labelled transferrin or albumin was detected in the fetal blood. The rate of transfer of iron from maternal plasma to the fetuses increased after the 25th day of pregnancy to reach a maximum at about the 54th day, and then decreased markedly by the 65th day.The effects of hypoxia and of metabolic inhibitors on iron transfer were studied by in vivo perfusion of the placenta. Reduction in 59Fe transfer was observed in animals breathing 10 or 15% oxygen in nitrogen, or when sodium arsenite (5 mM), sodium cyanide (10 mM) or 2,4‐dinitrophenol (10 mM) were added to the perfusate.The results indicate that maternal plasma transferrin is an adequate source of iron for the fetal guinea pig, and that placental transfer of iron is an active process, dependent on cellular metabolism, in which maternal plasma transferrin is taken up by the placenta followed by removal of the iron from the transferrin and transfer to the fetal blood.
THE PERMEABILITY OF INDIVIDUALLY PERFUSED FROG MESENTERIC CAPILLARIES TO T1824 AND T1824‐ALBUMIN AS EVIDENCE FOR A LARGE PORE SYSTEM
Authors: Levick J. R. , Michel C. C. 
Published: December 2014

Landis [1963, 1964] perfused single capillaries of the frog mesentery with Ringer solutions containing T1824 and bovine albumin, and observed spots of dye outside the vessels within a few seconds. He suggested these localized regions of high permeability might represent the large pores which have been proposed to account for the permeability of normal capillaries to large protein molecules. Binding curves of T1824 to bovine albumin reported in the present paper (which confirm the results of others) suggest that 50% of the T1824 in the perfusates used by Landis was in an unbound state. The free diffusion coefficients of T1824 and T1824‐albumin complex have been measured and found to be 1·64 10‐6 cm2 sec‐1 for T1824 and 0·59 10‐6 cm2 sec‐1 for T1824‐albumin complex. Stokes‐Einstein radii calculated from the free diffusion coefficients are 1·31 nm for T1824 and 3·62 nm for T1824‐albumin complex; thus unbound T1824 may be regarded as a small molecule.When individual capillaries of frog mesentery were perfused via a micropipette with Ringer solution containing T1824 and no albumin, dye escaped from the vessels within the first 30 sec in twenty‐six out of thirty‐one perfusions. When capillaries were perfused with solutions containing T1824‐albumin complex and no unbound dye, no dye left the capillaries during the first 30 sec in forty‐three out of forty‐seven perfusions.In thirteen experiments in which the same capillary was perfused separately with Ringer solutions containing T1824‐albumin complex and no free dye, and with T1824 and no albumin, dye crossed the capillary walls during the first 30 sec of perfusion only when free dye was present. In seven experiments the rate of passage of T1824 was compared when the same vessel was perfused with T1824 and a solution of T1824‐albumin complex and an excess of unbound T1824. These experiments indicate that T1824‐albumin complex slows the movement of T1824 across the capillary wall.Since the rapid movement of dye out of capillaries is seen only when perfusates contain unbound T1824, it is concluded that Landis's observations indicate non‐uniform permeability to small molecules and may not be used as evidence for a large pore system.
RENAL EXCRETION OF SODIUM AND SODIUM TOLERANCE IN THE PIG
Authors: Mason G. D. , Scott D. 
Published: December 2014

Young pigs averaging 25 kg liveweight were given supplements of up to 1·7 mole of sodium chloride in their food each day. Excretion of sodium in both urine and faeces was increased but the bulk of the supplements were excreted in the urine, demonstrating the importance of the kidney in the elimination of dietary sodium excess. Glomerular filtration rate was increased and the proportion of filtered sodium reabsorbed was reduced during supplementation.Intravenous infusions of hypertonic sodium chloride solutions at rates up to 9·2 m‐mole/min for 3 hr resulted in increases in the concentration of sodium in the plasma and increases in both sodium and calcium excretion in the urine. Excretion of potassium was unaffected.These results indicate that pigs can tolerate large amounts of sodium chloride provided that drinking water is freely available.
A PHARMACOLOGICAL AND HISTOLOGICAL INVESTIGATION OF THE INVOLVEMENT OF MAST CELLS IN CUTANEOUS AXON REFLEX VASODILATATION
Authors: Kiernan J. A. 
Published: December 2014

Arteriolar vasodilatation following injury to the pinna of the left ear was measured thermometrically in 43 rats. Quantitative histological assessments were made of the intact and degranulating dermal mast cells in the left and right ears of the animals. Vasodilatation, with associated increased proportions of degranulating mast cells, was found only in animals in which the sensory innervation of the left ear was intact, allowing the occurrence of axon reflexes.In rats depleted of mast cells by treatment for 5 days with compound 48/80, axon reflex vasodilatation was suppressed, indicating that mast cells are essential for the development of the flare in the triple response. Vasodilatation was also suppressed in animals injected with aspirin 20—30 min prior to injury. In these latter rats, there was no increase in the proportion of degranulating dermal mast cells It is suggested that aspirin protects the mast cells from the degranulating effect of axon reflexes.These results indicate that the arteriolar flare around the site of a cutaneous injury is mediated by the action of axon reflexes upon dermal mast cells. This conclusion is discussed in relation to other observations on vasodilatation in injured and diseased skin.
RENAL REGULATION OF PHOSPHATE EXCRETION IN THE PIG
Authors: McIntosh G. H. , Scott D. 
Published: December 2014

Young pigs of about 25 kg in weight were given supplements of Na2HPO4 either in their food or by intravenous infusion and the effects on urinary phosphate excretion were studied. The results obtained showed that the amount of inorganic phosphate excreted in the urine increased with increase in the amount of phosphate filtered at the glomerulus. A threshold value for phosphate excretion in these pigs occurred at a plasma concentration of 2·03 mmol/l. while over a wide range of filtered phosphate load (0·21–1·14 mmol/min) phosphate was reabsorbed at a mean maximum rate of 0·19 mmol/min.Parathyroidectomy did not alter the relationship between phosphate excretion and filtered phosphate load which suggests that in the pig adjustment of renal phosphate excretion in relation to filtered load is not dependent upon parathormone.
MAST CELLS AND GASTRIC SECRETION IN THE RAT
Authors: Heap B. J. , Kibrnan J. A. 
Published: December 2014

Gastric secretion of acid was measured in adult rats deprived of solid food for 48 hr. In control animals, values were obtained for the residual content of acid in the stomach, indicative of the rate of basal secretion, and for the quantities of acid secreted in 30 min following injections of histamine, pentagastrin, insulin and compound 48/80. The same measurements were made in groups of rats treated for 5 days with compound 48/80 (a regime which depleted the whole body of mast cells) and for 3 days with dexamethasone (which selectively depleted the gastric mucosa of mast cells). The content of residual acid was depressed to one third of the control value in the 48/80‐treated rats, but the additional secretion due to histamine, pentagastrin or insulin was unaffected. A secretory response to a single injection of compound 48/80 could not be obtained in rats depleted of mast cells. In the dexamethasone‐treated rats, the residual level of acid was increased to 1·5 times the control value, but the magnitudes of the responses to secretogogues were unchanged.It is concluded that basal secretion of acid into the stomach of the rat is stimulated by histamine derived from mast cells throughout the body, those of the gastric mucosa having no special significance in this respect. Mast cells are not involved in the mediation of the secretagogue actions of exogenous histamine, pentagastrin and insulin, but the present results do not preclude the participatiort of histamine from sources other than mast cells in the process of gastric secretion.
SECRETORY AND STRUCTURAL EFFECTS OF 6‐HYDROXY‐DOPAMINE ON NORMAL PAROTID GLANDS OF RATS, AND AT DIFFERENT TIMES AFTER SURGICAL SYMPATHECTOMY
Authors: Thulin A. , Garrett J. R. 
Published: December 2014

The effects of i.v. 6‐hydroxydopamine (6‐OHDA), 100 mg/kg, have been studied on parotid glands of rats at 12, 24, 48, 72 hr and 3 weeks after avulsion of the right superior cervical sympathetic ganglion. The salivary flow from normal left control glands and from right glands 12 hr after ganglionectomy were similar, but at longer times after ganglionectomy the secretory response from the test glands was greatly reduced.Morphological assessment showed that 6‐OHDA induced a massive depletion of secretory granules from all control glands and also at 12 hr after ganglionectomy but at 48 and 72 hr there was considerably less depletion of granules on the ganglionectomized side.It is thought that at the longer times after ganglionectomy the secretion from the test glands is caused by circulating catecholamines released by the action of 6‐OHDA on adrenergic nerves elsewhere, plus a possible small direct secretogogue effect of 6‐OHDA. The additional effects on the normal side and at 12 hr after ganglionectomy are thought to be attributable to the release of catecholamines from adrenergic nerves within the gland.
THE EFFECT OF CHOLESTEROL OLEATE TREATMENT OF MICE ON THE ROSETTE FORMING CELL RESPONSE AGAINST SHEEP ERYTHROCYTES
Authors: Smith I. I. , Dewar A. Edna , Ramage Elizabeth F. , Stuart A. E. , Adams W. 
Published: December 2014

Mice injected with a single dose of 60 mg cholesterol oleate emulsion showed substantial blockade of the mononuclear phagocyte system, measured by the rate of vascular clearance of radio‐labelled sheep erythrocytes. The labelled erythrocytes, in lipid treated mice, localized mainly in the spleen, contrasting with control mice in which localization was mainly in the liver.Treatment with this lipid, 24 hr before the intravenous injection of two different doses of sheep erythrocytes, resulted in significant depression of the rosette forming cell response in the spleen, whereas the responses in the lymph nodes of both control and lipid treated mice were at a low level and not significantly different. Intravenously administered cholesterol oleate emulsion is known to localize mainly in the Kupffer cells and in splenic red pulp macrophages. Cultured macrophages treated with this lipid show inhibition of antigen‐binding and depressed phagocytosis of heterologous erythrocytes. The lipid does not affect lymphocytes.These findings are in keeping with the hypothesis that macrophages play a direct role in the induction of an immune response against a particulate antigen.