bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Haemorrhage in Rats Lacking Vasopressin (Brattleboro Strain): Influence of Naloxone
Authors: Gardiner S. M. , Bennett T. 
Published: August 2015

1. The effects of naloxone on blood pressure recovery after either rapid arterial haemorrhage or prolonged venous haemorrhage were studied in rats lacking vasopressin (Brattleboro strain) and in control (Long Evans) rats.
2. To produce similar reductions in blood pressure, less blood had to be taken from the Brattleboro rats than from the Long Evans rats.
3. After rapid arterial haemorrhage in the absence of naloxone, blood pressure recovery was slower in Brattleboro rats than in Long Evans rats. Naloxone did not affect the response to rapid arterial haemorrhage in Long Evans rats, but improved blood pressure recovery in Brattleboro rats; despite this improvement, the Brattleboro rats remained hypotensive at a time when the Long Evans rats were normotensive. These findings suggest that both the absence of vasopressin and a depressor action of β-endorphins may contribute to the poor ability of Brattleboro rats to cope with rapid haemorrhage.
4. After prolonged venous haemorrhage in the absence of naloxone, there was no difference between the recovery of blood pressure in Brattleboro rats and Long Evans rats. Naloxone improved blood pressure recovery to a similar extent in both strains of rat. These findings suggest that the absence of vasopressin does not impair blood pressure recovery after prolonged haemorrhage.
Surgical Reversal of Renovascular Hypertension in Rats: Changes in Blood Pressure, Plasma and Aortic Renin
Authors: Brice Joan M. , Russell G. I. , Bing R. F. , Swales J. D. , Thurston H. 
Published: August 2015

1. Blood pressure, plasma and aortic renin concentrations were measured in Goldblatt two-kidney one-clip hypertensive rats before and after surgical correction by removing the renal artery clip.
2. Blood pressure fell rapidly in the first hour and then more slowly over 24 h.
3. Plasma renin concentration fell into the normal range by 3 h after unclipping.
4. Aortic renin concentration was markedly raised in hypertensive rats and declined slowly after unclipping, being virtually unchanged at 3 h and reaching normal levels at 24 h.
5. The fall in blood pressure produced by removal of the renal artery clip in Goldblatt two-kidney one-clip hypertensive rats does not depend upon the renin-angiotensin system in plasma and vascular tissue and indicates that a renal vasodepressor system may be involved.
T-Lymphocyte Subsets in Adult Coeliac Disease
Authors: Corazza G. R. , Tabacchi P. , Frisoni M. , Londei M. , Bastia D. , Gasbarrini G. 
Published: August 2015

1. As a defect of suppressor function has been hypothesized in the pathogenesis of coeliac disease, we measured, by monoclonal antibodies, the inducer/suppressor T-cell ratio in adult coeliac disease.
2. No statistical difference was observed between coeliac patients and healthy controls, irrespective of treatment and HLA status.
3. These results do not show an imbalance in the inducer/suppressor T-cell ratio in coeliac disease.
Calcium Transport in Synaptosomes and Subcellular Membrane Fractions of Brain Tissue in Spontaneously Hypertensive Rats
Authors: Kravtsov G. M. , Orlov S. N. , Pokudin N. I. , Postnov Yu. V. 
Published: August 2015

1. The uptake of Na+ and Ca2+ by synaptosomes and uptake of Ca2+ by the mitochondria and microsomes of brain tissue of rats with spontaneous hypertension (SH rats) and normotensive Kyoto-Wistar rats (WKY rats) were studied with an isotope-exchange method.
2. By means of inhibitor analysis it has been shown that calcium influx into the synaptosomes during depolarization of their plasma membrane takes place only through the potential-dependent channels in both groups of animals.
3. Basal Ca2+ uptake by the synaptosomes of hypertensive rats was increased, apparently by partial depolarization of the synaptosome membrane caused by the increased membrane permeability to Na+ (basal Na+ uptake by synaptosomes was found to be increased in hypertensive rats).
4. Ca2+ uptake by mitochondria of hypertensive rats was increased, and the Ca2+ uptake by microsomes was decreased in these rats compared with controls.
5. The increment of the maximal Ca2+ transport rate in microsomes after the addition of calmodulin was decreased in spontaneously hypertensive rats compared with normotensive animals. Thus alterations in the interaction of calmodulin with the Ca2+-transporting systems of the plasma membrane are an important part of the widespread membrane defect observed in spontaneous hypertension.
6. The changes in the Ca2+-transporting and Ca2+-regulating systems of the synaptosomes of brain tissue in spontaneously hypertensive rats may be the basis for the increase of the intrasynaptosomal Ca2+ concentration and, in turn, for the alteration in the rate of neurotransmitter release.
Assessment of Gall-Bladder Storage Function in Man
Authors: Jazrawi R. P. , Kupfer R. M. , Bridges C. , Joseph A. , Northfield T. C. 
Published: August 2015

1. We have validated a scintiscanning method for measuring fasting-state gall-bladder (GB) filling in man. 99mTc-labelled diethyl phenylcarbamoylmethyliminodiacetate (Tc-HIDA) was given intravenously, and 90 min later GB and gut activity were measured by using two isosensitive rectilinear scanning heads (anterior and posterior). Studies with a phantom GB in vitro, and studies in man in vivo, showed that the maximum error due to differences in isotope depth was 8%, compared with 300% when only one head was used.
2. By combining this technique with measurement of biliary lipid concentrations of fasting-state GB bile obtained by nasoduodenal intubation and intravenous cholecystokinin infusion, we were able to measure for the first time the total mass of all three biliary lipids in the GB. GB bile samples obtained in this way were divided into three consecutive portions of equal size in order to assess GB mixing. Bile acid pool size was also measured by isotope dilution.
3. We studied 12 healthy non-obese men. Fasting-state GB filling over 90 min (mean ± sem) was 54 ±8%. Biliary lipid mass in GB was 4.9 ±0.5 mmol for bile acids (67 ± 5% of the total bile acid pool), 1.6 ±0.2 mmol for phospholipid and 0.5 ± 0.1 mmol for cholesterol. The three consecutive portions of fasting GB bile gave values of 1.05 ± 0.07, 1.05 ± 0.06 and 1.03 ±0.10 for cholesterol saturation index (SI) and 6.6 ±1.1, 7.4 ± 1.6 and 6.5 ± 1.0 for Tc-HIDA c.p.m. × 1000 per mmol of bile acids.
4. The SI of fasting-state GB bile was significantly correlated with fasting-state GB filling (r = 0.63; P &lt; 0.05). It was also correlated with cholesterol mass in GB (r = 0.64; P &lt; 0.05), but not with bile acid and phospholipid mass.
5. We conclude that: (a) valid measurements of GB filling can be made in man by a simple scintiscanning technique employing 99mTc-HIDA as a biliary marker; (b) biliary lipid mass can also be measured if GB bile is obtained; (c) SI in health is in part determined by the degree of fasting-state GB filling, and in part by cholesterol mass in GB; (d) fasting-state GB content is well mixed in health.
The Effects of Captopril on the Acute Vascular Responses to Frusemide in Man
Authors: Johnston G. D. , Nicholls D. P. , Leahey W. J. , Finch M. B. 
Published: August 2015

1. To examine the importance of angiotensin II formation in the production of frusemide's acute peripheral venous and arterial responses, the effect of pretreatment with captopril was studied.
2. Captopril abolished the acute increases in venous capacitance and blood pressure and attenuated the increases in forearm vascular resistance produced by intravenous frusemide.
3. The study provides evidence that angiotensin II formation performs an essential role in the production of the acute vascular effects of frusemide in man.
Control of Skeletal Muscle Blood Flow during Postural Changes in Acute Myocardial Infarction
Authors: Skagen K. , Henriksen O. 
Published: August 2015

1. Central and local regulation of skeletal muscle blood flow in the leg was studied in the acute phase of myocardial infarction.
2. Blood flow was measured by the local 133Xe washout technique in the anterior tibial muscle.
3. The vasoconstrictor response to increase in venous transmural pressure was not present on day 1 after coronary occlusion but gradually returned during days 2, 3 and 7.
4. A normal response to decrease in arterial perfusion pressure was observed, suggesting that intrinsic vascular reactions responsible for autoregulation of blood flow were not affected in the acute phase of myocardial infarction.
5. Passive head-up tilt (30°) induced vasoconstriction in skeletal muscle tissue. There were no differences in this response at any time during the course of acute myocardial infarction.
6. The abolition of the vasoconstrictor response to increase in venous transmural pressure on day 1 is most likely due to centrally elicited increase in sympathetic activity as a normal vasoconstrictor response was obtained the following days. Decrease in baroreceptor activity induced by head-up tilt enabled a marked neurogenically mediated vasoconstriction in skeletal muscle tissue which was almost unaffected during the course of myocardial infarction.
The Rising Ventilatory Cost of Bicycle Exercise in the Seventh Decade: A Longitudinal Study of Nine Healthy Men
Authors: Patrick J. M. , Bassey E. J. , Fentem P. H. 
Published: August 2015

1. Submaximal bicycle exercise tests have been performed in nine healthy men on seven annual occasions between the ages of 64 and 70 years. Ten younger men (average age 33 years) have also been studied once for comparison.
2. The ventilatory cost of submaximal work at V̇o2 = 1 litre/min rises significantly from 24.3 ±0.8 litres/min at age 64 years to 31.8 ± 1.8 litres/min at age 70 years; the latter value differs significantly from that of the young men (25.6 ± 0.9 litres/min). Similar changes are seen in the ventilation at 75 W and at V̇co2 = 1 litre/min. The rate of change, between 3% and 5% per year, is considerably greater than that found for the change with age in cross-sectional studies of younger men. There is also a rise in the respiratory quotient, consistent with the hyperventilation found.
3. The cardiac frequency at 1 litre/min also rose with age in the older men, and rough estimates of the decline in their aerobic capacity suggest that progressive anaerobiosis could account for at least some of this increase in ventilation seen during submaximal work.
Role of Prostacyclin in Blood Pressure Regulation and Aldosterone Production in Conscious Rabbits
Authors: Miyamori Isamu , Morise Toshio , Ikeda Masatoshi , Koshida Hideo , Takeda Yoshiyu , Yasuhara Shuichiro , Takimoto Hiroaki , Takeda Ryoyu 
Published: August 2015

1. The effects of subdepressor infusion of prostacyclin (PGI2, 5.3 pmol min−1 kg−1) on arterial pressure and aldosterone production induced by angiotensin II (ANG II) were studied in conscious rabbits.
2. Indomethacin pretreatment caused an augmented blood pressure response after ANG II infusion, which returned to near control level after concomitant infusion of a subdepressor dose of PGI2.
3. Aldosterone production after ANG II was significantly attenuated after pretreatment with indomethacin. PGI2 infusion restored this reduced response to near control level.
4. These results may suggest that PGI2 in the circulation could also serve to modulate the pressor and hormonal action(s) of ANG II.
Glomerular Ultrafiltration and Tubular Reabsorption of Bovine Serum Albumin and Derivatives with Increased Negative Charge in the Normal Female Wistar Rat
Authors: Lawrence Gillian M. , Brewer Douglas B. 
Published: August 2015

1. Urinary clearances of bovine albumin derivatives rose with their increasing negative charge.
2. A mathematical model has been developed to assess the relative contributions of glomerular ultrafiltration and tubular reabsorption to overall urinary protein clearance.
3. This model indicates that the increased urinary clearance seen with negatively charged bovine albumin derivatives was due to a large reduction in the amount of protein absorbed by the proximal tubular epithelium, which swamped the effects of a small decrease in glomerular ultrafiltration.
4. Derivatives of bovine albumin with increasing negative charge were also cleared with correspondingly greater rapidity from the blood stream.
Glycine Pools and Turnover Rates in Leukaemia Patients Measured with [15N]Glycine
Authors: Lapidot Aviva , Nissim Itzhak , Shaklai Matityahu , Samuel Ruth , Liberman Uri A. 
Published: August 2015

1. Turnover parameters for plasma glycine were measured by administration of a single dose of [15N]glycine to overnight fasted healthy volunteers, nine patients with chronic leukaemia, one patient with acute monocytic leukaemia and one patient with chronic myeloid leukaemia before and after chemotherapy.
2. Gas chromatography-mass spectrometry was used to determine plasma [15N]glycine enrichment. Pool sizes and turnover rate constants were estimated from time-decay curves for isotope enrichment.
3. Turnover rate constants and metabolic clearance rates of plasma glycine in leukaemia patients were elevated in comparison with data for healthy volunteers. The increased rates of glycine disappearance from the circulation were not accompanied by a depletion in glycine pool size. Turnover rate constants fell during chemotherapy and were within the normal range during remission.
4. There was a significant positive correlation between glycine turnover rate constants and leucocyte counts.
5. The increase in glycine turnover rate constants may be related to proliferation of the neoplastic cells.
The Measurement of Whole Body Protein Turnover in the Preterm Infant with Intragastric Infusion of l-[1-13C]Leucine and Sampling of the Urinary Leucine Pool
Authors: De Benoist B. , Abdulrazzak Y. , Brooke O. G. , Halliday D. , Millward D. J. 
Published: August 2015

1. The measurement of whole body protein turnover in the preterm infant has been investigated with an intragastric infusion of L[1-13C]-leucine and with sampling of the urinary leucine pool.
2. Measurements have been made in seven preterm infants with body weights averaging 1733 g, fed with either human breast milk (n = 3) or proprietary formulae (n = 4), giving intakes of 541 (±25)kJ/kg and 465 (±42)mg of N day−1kg−1 and growing satisfactorily (14.7 ± 2.6 g day−1 kg−1).
3. The measurement of the enrichment of urinary leucine was well within the capability of gas chromatography-spectrometry, and similar values for the enrichment of plasma and urinary leucine were observed (plasma/urinary ratio was 0.93 ± 0.04, mean ± 1 sem, n = 13). Isotopic equilibrium, as indicated by a plateau in the urinary leucine and expired CO2 enrichment, was obtained within 8 h and was maintained for at least 48 h.
4. Nitrogen retention, measured by nitrogen balance, was similar to that calculated from the leucine retention (determined as the leucine intake — oxidation), i.e. 310 ± 45 and 301 ± 38 mg of N day−1 kg−1 (means ± 1 sem). Because of this it is suggested that in this specific type of study the direct measurement of nitrogen retention dispenses with the need for measurement of leucine oxidation, thereby simplifying the measurements.
5. From the leucine flux, leucine intake and nitrogen retention, rates of whole body protein synthesis and degradation were shown to be 11.32 (±0.78) and 9.54 (±0.55) g day−1 kg−1.
Ephedrine-Induced Thermogenesis in Man: No Role for Interscapular Brown Adipose Tissue
Authors: Astrup A. , Bülow J. , Christensen N. J. , Madsen J. 
Published: August 2015

1. The warmest interscapular skin areas were located by thermography in six healthy subjects during ephedrine-induced thermogenesis.
2. In these interscapular areas, and in lumbar control areas, the skin temperature, subcutaneous temperature and adipose tissue blood flow were measured before and during ephedrine-induced thermogenesis.
3. The skin and subcutaneous temperatures increased in the interscapular area as well as in the lumbar area, by about 0.7-1.2°C. The interscapular skin temperature remained about 1°C higher than the lumbar; the subcutaneous temperatures in the two areas were identical during the experiments.
4. Although the interscapular subcutaneous adipose tissue blood flow increased about sixfold and the lumbar increased twofold, the absolute flows were higher in the lumbar area.
5. The oxygen uptake increased to a maximum of 30% above control level.
6. Plasma glucose and glycerol concentrations remained unchanged, and plasma non-esterified fatty acids, lactate and noradrenaline concentrations increased slightly but significantly.
7. Biopsies taken from the hot interscapular areas did not contain brown adipose tissue.
8. It is concluded that the high interscapular skin temperature may be due to a lower insulating fat thickness and that the increases in skin and subcutaneous temperatures during ephedrine-induced thermogenesis are caused by an increased blood flow. These observations weigh against the hypothesis that the interscapular temperature increase is due to functional, interscapular brown adipose tissue.
Whole Body Nitrogen Kinetics in Man: Determination from Plasma [Guanidino-15N]Arginine
Authors: Yudkoff Marc , Nissim Itzhak , Glassman Mark , Segal Stanton 
Published: August 2015

1. Whole body nitrogen turnover and protein synthesis were calculated by the method of D. Picou & T. Taylor-Roberts [Clinical Science and Molecular Medicine (1969) 36, 283–296] except that plateau plasma enrichment of [guanidino-15N]arginine was used in place of the [15N]urea enrichment after a constant infusion of [15N]-glycine. With this approach metabolic pool turnover and protein synthesis were 637.2 ± 73.0 mg of N day−1 kg−1 and 2964.0 ± 409.5 mg of protein day−1 kg−1 respectively.
2. Virtually identical isotopic enrichment in [guanidino-15N]arginine and [15N]urea were observed in a healthy young adult who took repeated oral doses of [15N]glycine for a period of 60 h: 0.47 (arginine) and 0.48 (urea) atom% excess.
3. The turnover of glycine nitrogen and of urea, determined from the constant infusion of [15N]glycine and [13C]urea, was 66.2 ± 3.3 mg of N day−1 kg−1 and 156.2 ± 4.3 mg of urea day−1 kg−1 respectively. The ratio of steady-state enrichment in arginine to that in glycine, reflecting the fraction of arginine derived from glycine, was 10.5%. By using the [guanidino-15N]arginine enrichment as representative of the expected enrichment in [15N]urea at plateau, it was calculated that approximately 25% of glycine N flux is directed toward the synthesis of urea, with the remainder directed to protein and quantitatively minor products like haem and creatinine.
4. Unlike steady-state [15N]urea labelling, which is achieved only after infusion of [15N]-glycine for several days, plateau isotopic abundance in [guanidino-15N]arginine was attained after only 1–2 h of [15N]glycine infusions, thereby allowing estimation of whole body nitrogen kinetics and the rate of transfer of glycine nitrogen to urea in a relatively brief experiment.
Effect of Clofibrate on the Metabolism of Bilirubin, Bromosulphophthalein and Indocyanine Green and on the Biliary Lipid Composition in Gilbert's Syndrome
Authors: Kutz Klaus , Kandler Harald , Gugler Roland , Fevery Johan 
Published: August 2015

1. Clofibrate (20 mg day−1 kg−1 body weight) given orally for 2 weeks to 18 subjects with Gilbert's syndrome reduced the total serum bilirubin concentration from 44.4 (22.1–71.7) μmol/l (median, range) to 15.0 (7.9–28.9) μmol/l, mainly by decreasing the ‘indirect’ fraction to 34.5% of pretreatment values.
2. In contrast to treatment with phenobarbitone, clofibrate did not change the ratio of bilirubin mono- to di-conjugates in bile.
3. The initial plasma disappearance rate of indocyanine green and of bromosulphophthalein did not show consistent changes during clofibrate treatment but the ‘apparent’ maximal biliary secretion capacity of bromosulphophthalein (Tm) decreased in most of the patients studied, whereas the relative storage capacity (S) tended to increase.
4. As expected, the cholesterol saturation of bile increased in all subjects.
5. These results suggest that clofibrate increases mainly the glucuronidation of bilirubin, promoting as such the overall hepatic transport in Gilbert's syndrome. However, it decreases the maximal biliary secretion of bromosulphophthalein, possibly by an increased hepatic retention. These phenomena might be linked to the augmented content of Z protein in the liver.
Inhibition of Partially Purified Rat Brain Na+, K+- Dependent Atpase by Bile Acids, Phenolic Acids and Endotoxin
Authors: Seda H. W. M. , Gove C. D. , Hughes R. D. , Williams Roger 
Published: August 2015

1. Sera from patients with fulminant hepatic failure (FHF) has previously been shown to contain substance(s) which inhibit leucocyte ouabain-sensitive sodium efflux and rat brain Na+,K+-dependent ATPase in vitro. Similar effects in the patients could be an important mechanism in the development of encephalopathy and cerebral oedema.
2. In previous studies, bilirubin, free fatty acids and mercaptans have been shown to inhibit Na+,K+-ATPase in vitro. The present report is concerned with the effects of a number of other potentially toxic substances present in the serum of patients with FHF.
3. Chenodeoxycholic acid, p-hydroxyphenyllactic acid, p-hydroxyphenylpyruvic acid and endotoxin caused 30–45% inhibition of partially purified rat brain Na+,K+-ATPase at concentrations known to occur in the serum of patients with FHF. At low concentrations the inhibitory effects of these substances were additive, but at higher concentrations a maximum level of inhibition was reached.
4. These further substances are likely, therefore, to be of importance in the disturbances of brain function found in FHF.
The Role of Corticosteroids in the Regulation of Myocardial Na, K-ATPase in Normotensive and Spontaneously Hypertensive Rats
Authors: Stern Naftali , Beck Frances W. J. , Chandler Donald Walt , Mayes Douglas M. , Sowers James R. 
Published: August 2015

1. Sodium, potassium-dependent adenosine triphosphatase (ATPase) of the renal tubule is known to be dependent on both gluco- and mineralo-corticoids. Recent evidence suggests that corticosteroids may modulate ATPase activity at extrarenal sites. The myocardium contains glucocorticoid receptors to which mineralocorticoids can also bind. Thus, the possibility that myocardial ATPase is corticosteroid dependent was examined in the Wistar-Kyoto (WKY) normotensive rat and also in the spontaneously hypertensive (SH) rat, a strain previously shown to exhibit reduced myocardial ATPase activity.
2. WKY and SH rats (in groups of 10) were either sham operated or adrenalectomized and placed on 1% NaCl solution as drinking water. Adrenalectomized rats subsequently received daily intraperitoneal injections of either vehicle (1% NaCl, 0.5 ml), aldosterone (30 μg/kg) or dexamethasone (60 μg/kg). Renal cortical and myocardial ATPase activities were determined 21 days later in all groups.
3. Adrenalectomized WKY rats had reduced myocardial ATPase activity (5.15 ± 0.88 vs 8.18 ± 0.93 μmol of phosphate h−1 mg−1 of protein in controls; P &lt; 0.01). This observed decrease in ATPase in adrenalectomized rats could be at least partly prevented by selective aldosterone or dexamethasone replacement. Parallel changes were observed with renal cortical ATPase.
4. SH rat myocardial ATPase was lower than in WKY rats (P&lt;0.05, 5.88 ± 0.99 μmol of phosphate h−1 mg−1 of protein) and was unaffected by adrenalectomy (5.47 ± 0.68 μmol of phosphate h−1 mg−1 of protein) whether accompanied by aldosterone (6.08 ± 0.68 μmol of phosphate h−1 mg−1 of protein) or dexamethasone (6.47 ± 0.84 μmol of phosphate h−1 mg−1 of protein) therapy or not. Renal cortical ATPase, however, exhibited corticosteroid dependency in the SH rats that resembled the pattern observed in WKY rats.
5. It is suggested that the lower ATPase activity observed in SH rats after the evolution of hypertension may result from decreased sensitivity to endogenous corticosteroids.