bluuebunny/crossref_metadata_2025 huggingface dataset:
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.
EXPERIMENTAL DROWNING: CORONARY HAEMODYNAMICS AND MYOCARDIAL METABOLISM IN THE DOG
Authors: Maxwell G. M.
Published: December 2014

Freshwater (4·5 ml./kg) or seawater (1·6 ml./kg) was given intratracheally in intact dogs to simulate some aspects of drowning; coronary sinus flow was measured by thermodilution flowmeter, vascular pressures by strain‐gauge, and cardiac output by dye‐curve. The experiments produced prolonged depression of oxygen saturation, transient hypercapnia, and a short‐lived decrease in pH. Cardiac output and coronary flow were greatly increased; the latter response could be substantially inhibited if oxygen was given to the animals. Arterial glucose, lactate, and pyruvate levels increased. The coronary sinus values were generally in correspondence. Cardiac oxygen extraction (vols. per 100 ml.) decreased but percentage oxygen extraction increased. External cardiac efficiency increased, apparently in association with a shift of myocardial metabolism to an anaerobic pathway.
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.
EFFECTS OF AGE AND ENVIRONMENTAL TEMPERATURE ON THE JUXTAGLOMERULAR APPARATUS OF HOUSE MICE
Authors: Barnett S. A. , Macadam R. F.
Published: December 2014

The kidneys of wild house mice, Mus musculus, L., aged 16, 28 and 100 weeks, were examined histologically, with special reference to the state of the juxtaglomerular apparatus (JGA). Some of the mice were kept in an environment at 21°C, others at −3°C. The percentage of glomeruli with JGAs containing cells with granulated cytoplasm was unaffected by environmental temperature, but declined with age. The decline was not related to the presence of inflammatory lesions or glomerular sclerosis.
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.
THE ONSET OF FUNCTIONAL CAPACITY IN FETAL GUINEA‐PIG PARATHYROID GLANDS
Authors: Graham R. W. , Scothorne R. J.
Published: December 2014

Parathyroid tissue or pharyngeal pouch tissue containing the presumptive primordium of parathyroid III from embryonic guinea‐pigs has been explanted to the chick chorioallantoic membrane in contact with a piece of neonatal rat parietal bone. Histological study of the conjoined grafts, removed 4–7 days later, showed bone resorption, indicative of parathyroid secretory activity, at developmental ages of 23 days and older.
SECRETORY ACTIVITY OF THE SUBMAXILLARY GLAND IN PREPUBERAL AND ADULT RATS OF BOTH SEXES
Authors: Perec C. , Bramuglia N.
Published: December 2014

The secretory responses of the submaxillary gland of prepuberal and adult rats of both sexes were studied by nerve stimulation and by giving sialagogues. The maximal secretory capacity per unit weight of gland was greater in adult males than in females, by 34 per cent after chorda‐lingual nerve stimulation and by 38 per cent after giving pilocarpine. The threshold dose of methacholine seemed less in prepuberal than in adult rats, but the threshold doses of sympathomimetic agents were similar in all groups. The response of the adult male's gland to methacholine (10 µg per kg body weight) was greater than that of the adult female's gland, both when measured per gland and when calculated per unit weight of gland.
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.
FETAL OXYGEN CONSUMPTION IN LATE GESTATION
Authors: Clapp James F. , Abrams Robert M. , Caton Donald , Cotter Julian R. , Barron Donald H.
Published: December 2014

In acute experiments the oxygen consumption (ml./min) of pregnant, lightly anesthetized ewes has been determined under steady state conditions before and after occlusion of the umbilical circulation with the fetus in utero. At the conclusion of the experiment the fetus was delivered and weighed. The regular decrease in oxygen consumption which occurred with this procedure was linearly related to the fetal weight over a 4 kg range. On the assumption that this decrease represented the oxygen consumption of the fetus during the control period, the rate of fetal oxygen consumption ranged from 7·7 to 11·3 ml./kg/min. These results are in good agreement with those previously obtained when the umbilical blood flow was estimated and the (V‐A)O2 determined across the umbilical circulation with the fetus in utero. They indicate that the oxygen consumption of the near term fetal lamb represents a significant fraction of maternal (6 to 22 per cent in this series) and is of the same order of magnitude as that of the newborn animal.
DISTRIBUTION OF HISTIDINE DECARBOXYLASE IN THE PREGNANT MOUSE KIDNEY
Authors: Henningsson S. S. G. , Rosengren Elsa
Published: December 2014

The rate of histamine formation (histamine forming capacity, HFC) was determined in serial sections of the kidney of pregnant mice and in alternate sections the number of glomeruli was assessed. A significant degree of correlation between the number of glomeruli and HFC was found indicating that in the pregnant mouse kidney histidine decarboxylase resides mainly in the cortex.
FUNCTION OF THE GALL BLADDER IN SHEEP
Authors: Caple Ivan , Heath Trevor
Published: December 2014

Bile collected from the gall bladder of sheep at surgery contained a higher concentration of solutes than hepatic bile collected at the same time. When 20 ml. bile was placed in the isolated gall bladder, fluid was absorbed at about 4 ml./hr in both sheep and dogs, and any absorption of lipids or bile salts was negligible. Pressure in the gall bladder of sheep fluctuated over a range of about 18 mm mercury: during fasting, pressure waves occurred at the rate of 3–6/hr and each lasted for five minutes; after feeding they became more frequent, and sometimes lasted for 20 min. Injection of acid into the duodenum was followed by an increase in the pressure in the gall bladder, and this response, like most of the spontaneous waves, could be almost eliminated by atropine. The gall bladder did contract in response to cholecystokinin‐pancreozymin, but this was not affected by atropine. It is concluded that the gall bladder in the sheep has appreciable absorptive and contractile activity. However, bile is produced at a more rapid and uniform rate in sheep than in animals with simple stomachs, and as a result in the sheep each unit volume of bile spends a shorter time in the gall bladder, and its organic constituents are concentrated to a smaller extent.
MATERNAL‐FETAL CALCIUM RELATIONSHIPS IN MAN
Authors: Tan Christine M. , Raman A.
Published: December 2014

The total and ionic calciuim levels of maternal and fetal sera were determined and a small concentration difference for ionic calcium was found to exist between these sera. It is suggested that this difference could be accounted for by a process of simple diffusion.
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.
RESPONSES OF HEPATIC MICROVESSELS
Authors: Ho Margaret S. L.
Published: December 2014

The response of microvessels of the intact liver to various stimuli was observed in the anaesthetized rat by a modified transillumination technique, permitting photomicrography at any time during the direct microscopic observation. Adrenaline and noradrenaline appeared to have direct constrictor action on the portal venous branches, hepatic sinusoids and hepatic venous branches. Acetylcholine appeared to have a slight direct constrictor action on the hepatic sinusoids. Electrical stimulation of hepatic nerves showed that intrahepatic vessels were under sympathetic nervous control. The results of ligation of portal vein and hepatic artery indicated the presence of arterio‐venous anastomoses. Hepatic sinusoids, portal venous branches and hepatic venous branches were observed at first to constrict and then dilate in severe haemorrhage and traumatic shock.
A STUDY OF THE HEPATIC MICROCIRCULATION
Authors: Ho Margaret S. L. , Ma Richard Y. P.
Published: December 2014

Hepatic microcirculation in the anaesthetized rat was observed microscopically with the use of television, the liver being transilluminated by a light guide to provide a cool and bright light source. The study showed that the hexagonal lobular pattern of intrahepatic structure suggested in histological section could also be seen in the trans‐illuminated liver in situ. No intermittent flow was seen in the main sinusoidal channels or in the interlobular portal or central veins, but intermittent flow was observed in some of the anastomosing sinusoids which connected the main sinusoidal channels. There was no evidence of a specific sphincter mechanism in any portion of the sinusoidal bed of the rat liver.
AEROBIC WORK CAPACITY IN YOUNG, UNTRAINED ASIAN MEN
Authors: Duncan M.
Published: December 2014

The range of variability in aerobic work capacity in young untrained Asian men was assessed by measurement of the oxygen cost of bicycling at increasing work loads. Related pulmonary and cardiovascular responses were studied. The results obtained were compared with reports on western populations. Aerobic capacity was lower in the subjects studied.
THE IMPORTANCE OF GLUCOSE IN THE OXIDATIVE METABOLISM OF THE PREGNANT UTERUS AND ITS CONTENTS IN CONSCIOUS SHEEP WITH SOME PRELIMINARY OBSERVATIONS ON THE OXIDATION OF FRUCTOSE AND GLUCOSE BY FETAL SHEEP
Authors: Setchell B. P. , Bassett J. M. , Hinks N. T. , Gramam N. McC.
Published: December 2014

The day after implantation of catheters under general anaesthesia, U·[14C] glucose was infused intravenously into four conscious ewes about 130 days pregnant, and into two fetuses about 130 days old. U·[14C] fructose was infused into three other similar fetuses. It could be calculated that the pregnant uterus with its contents derived about 40% of its CO2 from blood glucose and oxidized directly about 45% of the glucose utilized. The total uptake of glucose by the uterus and contents accounted for about 70% of the glucose metabolism of the pregnant ewes, but the proportion of CO2 derived by the pregnant ewes from glucose was no higher than for non‐pregnant ewes or rams. The total oxygen consumption of uterus and contents was comparable to the extra oxygen used by a ewe when pregnant, as measured by calorimetry. The specific radioactivity of fetal blood fructose was still only about 60% of that of maternal blood glucose after 5 hours infusion which suggests that there are other precursors for fetal fructose besides maternal glucose. [14C] from fructose and glucose infused into the fetus was converted into CO2 and glycogen and [14C] from fructose was converted to glucose by the fetus or placenta. The degree of incorporation of both sugars into CO2 and glycogen was similar but neither sugar could account for more than a fraction of the CO2 production.
BRANCHING MONONUCLEAR CELLS IN THE FORESTOMACH EPITHELIUM OF THE SHEEP
Authors: Steven D. H. , Marshall A. B.
Published: December 2014

Branching cells are distributed at irregular intervals throughout the basal layers of the forestomach epithelium of sheep and certain other ruminants. In size, shape and ultrastructural appearance they are markedly different from the epithelial cells which surround them; there is, moreover, clear evidence to suggest that they are capable of amoeboid movement. Branching cells have many characteristics in common with leucocytes of the mononuclear series, and in particular with the monocyte of circulating blood. It appears that their most probable function is the interception of small quantities of antigenic material which have passed through defects in the absorption barrier into the intercellular space.
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.
INTRINSIC CONTRACTILITY OF LYMPHATICS IN SHEEP AND IN DOGS
Authors: Campbell Terence , Heath Trevor
Published: December 2014

Intralymphatic pressures were monitored from plastic cannulas implanted in the thoracic, lumbar trunk and mesenteric lymphatics of conscious and anesthetized sheep, and in the thoracic duct of anaesthetized dogs. Extrinsic factors appeared to be important in the propulsion of lymph only in the thoracic duct of the dog. Intrinsic pulsatile pressure patterns were recorded from all lymphatics studied in sheep, and from the thoracic duct in one out of three dogs. The pulses ranged from about 1–15 mm Hg in amplitude and from about 2–20 pulses/min in frequency. A parameter of contractility was defined and used to establish the existence in sheep of a linear relationship between contractility and flow rate. This relationship was demonstrated when flow was increased by infusion into the lymphatic or into a vein, or, in the case of mesenteric lymphatics, by feeding fat. It was concluded that the intrinsic contractility is myogenic in origin and is the major factor responsible for lymph propulsion at least in sheep; the relationship between contractility and flow enables the rate of lymph flow to keep pace with the rate of lymph production.
RENAL AND SALIVARY RESPONSES TO INFUSION OF POTASSIUM CHLORIDE, BICARBONATE AND PHOSPHATE IN MERINO SHEEP
Authors: Beal A. M. , Budtz-Olsen O. E. , Clark R. C. , Cross R. B. , French T. J.
Published: December 2014

The excretion of electrolytes was measured during infusion of isosmotic NaCl and hyperosmotic NaCl, KCl, KHCO3 and KH2PO4. The increases in G.F.R., urine flow and urinary excretion of potassium, sodium, chloride, bicarbonate and solute during the infusion of potassium salts were significantly greater than those during the isosmotic and hyperosmotic NaCl infusions; this finding excludes the rate of infusion and hyperosmolality of infusate as major contributors in the response to potassium infusion. The renal clearance of potassium was significantly higher in the sheep receiving the bicarbonate salt than in the animals receiving the chloride or the phosphate salts. Potassium bicarbonate loading was associated with low chloride excretion and potassium phosphate loading with low bicarbonate excretion. Potassium loading resulted in high rates of bicarbonate excretion in some experiments, which indicates a reduction in solute reabsorption in the proximal tubule. During the potassium infusions, the urinary calcium excretion rate and urinary pH were inversely correlated, renal magnesium excretion was not altered significantly and phosphate excretion was increased only when phosphate was infused. Salivary potassium secretion was highest in the phosphate‐loaded sheep and potassium retention was lowest in the sheep receiving KCl infusions.
EFFECTS OF RUMINAL HYPEROSMOLALITY ON THE ULTRASTRUCTURE OF RUMINAL EPITHELIUM AND THEIR RELEVANCE TO SODIUM TRANSPORT
Authors: Gemmell R. T. , Stacy B. D.
Published: December 2014

The keratinizing epithelium of the rumen is involved in maintaining a potential difference across the rumen wall. Addition of a low dose of KCl (150–250 m‐equiv) to the rumen causes an increase in the width of the intercellular spaces surrounding the basal cells; but further increase of the osmolality of the ruminal contents brings about the breakdown of the stratum granulosum and a decrease in the potential difference across the rumen wall. These changes are discussed in relation to sodium transport across the rumen wall. Zonulae occludentes have been consistently detected in the outermost layer of the stratum granulosum, and the present results indicate that these junctional complexes constitute a permeability barrier to the transepithelial movement of sodium.
BASAL AND POSTPRANDIAL PANCREATIC SECRETION IN RATS
Authors: Shaw H. M. , Heath T. J.
Published: December 2014

When pancreatic juice which was collected separate from bile was diverted from the duodenum of rats for 24 hr, the basal flow rate of juice and its output of protein increased greatly over values recorded immediately after operation. Similar increases were recorded when pancreatic juice was recirculated back into the duodenum for 24 hr. Infusion of bicarbonate or enzyme into the duodenum failed to affect these increases in secretion. Thus the hypersecretion of juice did not appear to be the result of loss of juice from the duodenum. Attempts were then made to estimate rates of pancreatic secretion without diverting bile from the common bile duct. Immediately after operation, rates of pancreatic secretion estimated indirectly from the differences between combined bile‐pancreatic juice and bile alone were higher than in those rats in which pancreatic juice was collected by diverting bile from the common bile duct. This suggested that bile in some way assisted the passage of viscous pancreatic juice down the common bile duct. Indirect estimates of pancreatic secretion made 24 hr after operation were greater than the estimates made immediately after operation but were similar to those values obtained after 24 hr in rats from which pure pancreatic juice was collected. This was taken as evidence to support the view that the trauma associated with anaesthesia and surgery may depress the rate of pancreatic secretion and that hypersecretion of juice may indeed be a normal phenomenon. In contrast to the situation reported to exist in dogs, indirect estimates of the effects of feeding on pancreatic secretion were similar irrespective of whether secretions were diverted from or returned to the duodenum.
REINNERVATION OF THE DENERVATED PAROTID GLAND OF THE CAT
Authors: Ekström J. , Emmelin N.
Published: December 2014

Functional recovery was studied in parotid glands of cats after cutting the auriculo‐temporal nerve. Denervation supersensitivity to methacholine started to decrease between 1 month and 2½ months after the operation, and at the same time there was an increase in the secretory responses to eserine, injected through the salivary duct. Reflexly induced secretion increased and the activity of choline acetyltransferase, greatly reduced shortly after the denervation, rose gradually. However, even a year or more after the denervation the reinnervation was incomplete.
THE SECRETORY INNERVATION OF THE PAROTID GLAND OF THE CAT: AN UNEXPECTED COMPONENT
Authors: Ekström J. , Emmelin N.
Published: December 2014

After section and degeneration of the auriculo‐temporal nerve in cats, parotid secretion could still be elicited by injecting eserine into the gland, by application of citric acid to the tongue or by electrical stimulation of afferent oral nerves, and choline acetyltransferase activity could be demonstrated in extracts of the gland. The secretion obtained was not mediated via sympathetic nerves, although electrical stimulation of such nerves caused some secretion from most glands. Cholinergic secretory fibres mainly or wholly responsible for the remaining secretion after section of the auriculo‐temporal nerve were traced along the internal maxillary artery.
THE EFFECT OF TETRODOTOXIN ON THE TRANSMEMBRANE POTENTIALS OF THE HEART CELLS
Authors: Nikitopoulou Georgia
Published: December 2014

The effect of tetrodotoxin on the transmembrane potentials of His‐Purkinje fibres and of myocardial cells in dog hearts has been examined. The Purkinje fibres appeared to be less susceptible to the action of tetrodotoxin than the ventricular cells. Tetrodotoxin 10–7 g/ml. irreversibly abolished the activity of ventricular cells, but 10–4 g/ml. was required to affect the production of action potentials in Purkinje fibres. Withdrawal of calcium ions probably facilitated the action of tetrodotoxin on Purkinje fibres.
ACID HYDROLASES IN THE RABBIT IN HAEMORRHAGIC SHOCK
Authors: Courtice F. C. , Adams E. P. , Shannon A. D. , Bishop D. M.
Published: December 2014

Haemorrhagic shock was induced in rabbits by removal of 20 to 33 ml./kg of blood in up to 5 hr. Following haemorrhage there were on average 4 to 5‐fold increases in the levels of β‐glucuronidase, N‐acetyl‐β‐D‐glucosaminidase, acid ribonuclease and cathepsin D in the circulating plasma. Acid phosphatase levels fell at first, approximately parallel with the fall in the level of protein, and rose only when the animal was near death from haemorrhagic shock. Several experiments in which thoracic duct and hepatic lymph were collected showed that the lymphatic pathway was not essential for the increased levels of acid hydrolases in the plasma following haemorrhage. Biochemical and histochemical studies on the liver and proximal ileum indicated an increased permeability of the lysosomal membranes in these two regions. The results pointed to the liver as the likely source of origin of the increased circulating plasma levels of acid hydrolases in the rabbit in haemorrhagic shock.
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 NOTE ON THE STORAGE OF IRON AS FERRITIN IN THE PROTEIN DEFICIENT RAT
Authors: El Din Achmed Nasr , Ramsay W. N. M.
Published: December 2014

1. The increased iron stored in the liver and spleen of the protein deficient rat is found in the form of ferritin to nearly the same extent as in the normal animal. 2. When the iron in the protein deficient diet is also increased, much of the additionally stored iron still appears as ferritin, especially in the liver. 3. The amounts of ferritin iron found in the liver are such that even the severely protein deficient rat probably provides more apoferritin than the normal animal.
EFFECT OF EXOGENOUS PROGESTERONE ON THE RATES OF UTERINE BLOOD FLOW AND OXYGEN CONSUMPTION OF SHEEP IN EARLY PREGNANCY
Authors: Caton D. , Abrams R. M. , Lackore L. K. , James G. , Barron D. H.
Published: December 2014

Progesterone was administered to 33 ewes which were between the 30th and 55th days of gestation, to see if it could change the rate (ml./kg/min) of uterine blood flow. In acute and in chronic experiments, rates were lower in treated animals. Administration of progesterone also appeared to be associated with a diminution in the rate of oxygen consumption (ml./kg/min) of the uterus and its contents. The significance of these observations to the interpretation of differences in rates of uterine blood flow and oxygen consumption which occur in normal pregnancy is discussed.
A DEVELOPMENT OF THE LANDIS TECHNIQUE FOR MEASURING THE FILTRATION COEFFICIENT OF INDIVIDUAL CAPILLARIES IN THE FROG MESENTERY
Authors: Michel C. C. , Mason J. C. , Curry F. E. , Tooke J. E. , Hunter P. J.
Published: December 2014

Two methods are described for measuring the filtration coefficient of individually perfused frog mesenteric capillaries. Both methods involve the perfusion of capillaries via a micropipette with a solution in which a small number of human red cells are suspended. After a short period of perfusion, the capillary is occluded at a point some 500 µm or more downstream from the point of cannulation. Movements of the red cells in the isolated capillary micropipette system are interpreted to be the consequence of fluid movements across the capillary wall. The filtration coefficient of the capillary is determined either (method I) from a series of different filtration rates measured at different capillary hydrostatic pressures when intracapillary colloid osmotic pressure is constant, or (method II) from the changes in filtration rate as the fluid within the capillary concentrates at a constant pressure. Values for the filtration coefficient obtained by both methods have a skewed distribution. Determinations made by method I at 14–16°C have a peak value of 2 x 10–3 µm.sec–1.cm H2O–1 and determinations made by method II at 22–26°C have a peak value of 5 x 10–3 µm.sec–1.cm H2O–1. The assumptions underlying both methods are discussed and a mathematical model of the change in protein concentration in a closed off capillary at constant pressure is presented in the appendix.
THE LIPASE ACTIVITY OF SHEEP PANCREATIC JUICE
Authors: Arienti G. , Harrison F. A. , Leat W. M. F.
Published: December 2014

Sheep pancreatic juice contains a powerful lipolytic enzyme which under optimum conditions can release 47·9 ± 2·0 µ‐equiv fatty acid/mg freeze dried pancreatic juice/min from a triglyceride/bile salt emulsion. The properties of this enzyme are consistent with those of lipase (EC3.1.1.3). The pH optimum of the lipase is 7·5 and negligible activity is found below pH5, suggesting that little hydrolysis of triglyceride can occur in the duodenum and upper jejunum of the sheep (pH 2·5‐5·0). The lipase is sensitive to acid in the range pH 2·5‐3·5. Pre‐incubation at pH 3·0 resulted in a 75% loss of lipase activity and at pH 2·5 practically all lipase activity was destroyed. The addition of duodenal secretions, bile and pancreatic juice increased the pH of abomasal digesta by 0·1, 0·3 and 0·1 units respectively, which was sufficient to protect most of the lipase from acid inactivation by abomasal digesta (pH 2·5).
SEPARATION OF THE PLACENTA IN THE EWE: AN ULTRASTRUCTURAL STUDY
Authors: Steven D. H.
Published: December 2014

Placental separation in the ewe appears to involve an explosive degeneration of the chorionic epithelium which occurs in the short space of time between parturition and the delivery of the fetal membranes. In the goat there is a similar mechanism of separation. By contrast separation of the placenta in the cow appears to depend upon a detachment at the junctional region between fetal and maternal epithelia. There is no obvious explanation for these findings. The results are discussed in the light of the placental hormonal environment in the period which immediately precedes parturition.
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.
UTILIZATION OF AMINO ACIDS BY THE ISOLATED PERFUSED SHEEP LIVER
Authors: Lindsay D. B. , Jarrett I. G. , Mangan J. L. , Linzell J. L.
Published: December 2014

To test Elwyn's suggestion [1970], that high concentrations of amino acids supplied to the liver from the hepatic artery do not stimulate protein synthesis, substrates containing amino acids have been infused into either the hepatic artery or portal vein of isolated sheep livers. The livers received highly oxygenated blood from the hepatic artery and partly deoxygenated blood from the portal vein. There were no significant differences in amino acid uptake (81 ± 4% of input), urea output (69 ± 6% of uptake) or ‘protein synthesis’ as assessed by N accumulation in the liver. Amino acids were actively extracted from the plasma by both routes of infusion and, when the concentrations simulated those occurring in the portal vein of fed sheep, the uptake was very similar to that in vivo. When an amino acid mixture based on that absorbed in dogs was infused, the extraction of individual amino acids was similar except for a negligible uptake of valine, leucine and isoleucine. In these experiments ‘protein synthesis’ was also very low.
PLASMA IRON TRANSPORT DURING EGG LAYING AND AFTER OESTROGEN ADMINISTRATION IN THE DOMESTIC FOWL (GALLUS DOMESTICUS)
Authors: Morgan E. H.
Published: December 2014

The concentrations of 59Fe and of radioiodinated transferrin and albumin were measured in the blood, liver, spleen, bone marrow and ova at different times after the injection of transferrin‐bound 59Fe and the labelled proteins into non‐laying, laying and oestrogen treated chickens. In the egg‐laying and oestrogen‐treated birds the 59Fe of the plasma was rapidly transferred from transferrin to another component with the properties of the phosphoprotein, phosvitin. Radioactive iron, and labelled transferrin and albumin to a lesser extent, entered the ova only while they were in the ovary. Relatively more labelled transferrin than albumin was found in all the tissues studied except in the ova, in which the two labelled proteins were present in the same relative concentration as in the plasma. It is concluded that, during egg laying and after oestrogen treatment, plasma iron bound to transferrin is taken up by the liver, incorporated into phosvitin and is then secreted into the plasma leading to elevation of the plasma iron concentration and transfer of iron to the ova.
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.
ISOLATION OF KALLIKREIN FROM MAMMARY GLAND OF COWS
Authors: Peeters G. , Verbeke R. , Houvenaghel A. , Reynaert R.
Published: December 2014

Small amounts of kallikrein were isolated from bovine mammary tissue. Immediately after slaughter, the udder was removed, perfused with ice‐cold xylocaine‐Rheomacrodex solution, and homogenized in ice‐cold acetic acid solution. Kallikrein‐like substances were adsorbed on DEAE‐cellulose, eluted with ammonium formate and fractionated by acetone precipitation. The 40—70% acetone fraction was separated on a Sephadex‐G 75 column and aliquots of each fraction were incubated for 1 or 2 hr with kininogen. After incubation, extracts were tested for kinin activity on the isolated rat uterus, the rat duodenum, blood flow through the femoral artery of dogs and by intramammary pressure assay in sheep. Release of kinins was demonstrated by all these techniques, highest kallikrein activity being detected in the molecular weight range 50,000 to 60,000. Direct injection of the enzyme into the udder artery of sheep, without prior incubation with kininogen, resulted in vasodilation and a rise in intramammary pressure. The kallikrein activity was strongly inhibited by aprotinin, but not by soybean trypsin inhibitor or ovomucoid. Kallikrein activity was always associated with esterase activity.