bluuebunny/crossref_metadata_2025_split huggingface dataset:
Failure of Loading with Sodium Bicarbonate to Protect against Acute Renal Failure Induced by Mercuric Chloride in the Rat
Authors: Beaumont J. E. , Kotchen T. A. , Galla J. H. , Luke R. G. 
Published: August 2015

1. To investigate the mechanism by which sodium loading protects against acute renal failure we compared the effects of prior chronic loading with NaCl, or with NaHCO3, on renal function after injection of HgCl2.
2. Twenty-four male Sprague-Dawley rats were divided into three groups of eight rats. One group drank isotonic NaCl solution, a second drank isotonic NaHCO3 solution and the third control group drank deionized water. Acute renal failure was induced by HgCl2 on day 9, and the rats were killed 48 h after injection.
3. Net sodium balances and plasma volumes were similar in both groups of sodium-loaded rats. After HgCl2 serum creatinine was significantly less and urinary volume was greater in NaCl-loaded than in both NaHCO3-loaded and water-drinking animals.
4. Plasma renin activity of both NaCl- and NaHCO3-loaded animals was less than that of control rats. However, renal renin content was suppressed by NaCl but not by NaHCO3 loading.
5. Loading with NaCl afforded greater protection against HgCl2-induced acute renal failure than NaHCO3. Since this difference was not related to changes in sodium balance or plasma volume before HgCl2, or plasma renin activity after HgCl2, the results support the hypothesis that intrarenal renin plays a role in the pathogenesis of HgCl2-induced acute renal failure in the rat.
The Effect of Disuse Muscular Atrophy on the Forces Generated in Dynamic Exercise
Authors: Sargeant A. J. , Davies C. T. M. 
Published: August 2015

1. Six patients were studied after prolonged immobilization of an injured leg resulting in muscle atrophy.
2. The forces exerted by the atrophied and normal legs during continuous dynamic exercise (one- and two-leg cycling) were examined by a specially adapted ergometer.
3. In one-leg cycling the peak force exerted on the crank at a given work rate, the net work rate performed on the crank, and the proportion of work rate performed in leg extension and flexion phases of the cycle were the same whether the atrophied or normal limb was used.
4. Despite these similarities there was an unexplained reduction in efficiency when using the atrophied leg to perform one-leg cycling.
5. In two-leg cycling the peak force exerted at a given work rate by the atrophied leg was reduced by about 40% as compared with the normal leg, which reflected a similar reduction in the contribution of that leg to the total net work rate. Possible reasons and implications for this disproportionate sharing of work between the normal and atrophied leg are discussed.
Evidence that ‘Inactive’ Renin is Produced outside the Kidney of the Rat
Authors: Vandongen R. , Poessée Marianne , Strang K. D. , Birkenhäger W. H. 
Published: August 2015

1. Inactive renin, which can be converted into an active form by acidification to pH 3·3, represents 4–63% of the total renin in rat peripheral plasma.
2. No inactive component could be found in the blood-free venous effluent of the perfused rat kidney before and after stimulation with isoprenaline.
3. This suggests a possible extrarenal source for inactive renin and may explain the presence of this component in anephric patients.
Influence of Ethanol on Non-Esterified Fatty Acid and Carbohydrate Metabolism during Exercise in Man
Authors: Juhlin-Dannfelt A. , Jorfeldt L. , Hagenfeldt L. , Hulten B. 
Published: August 2015

1. The influence of ethanol administration on the metabolism of non-esterified fatty acids (NEFA) and on the utilization of blood-borne substrates and stored glycogen by leg muscles was examined in nine young healthy subjects at rest and during 40 min bicycle ergometer exercise at 50% of maximal capacity. Ethanol was administered by a constant-rate intravenous infusion (6 mmol/min), giving an arterial concentration within the range of 9·3–15·6 mmol/l. Turnover of NEFA and regional exchange were evaluated with [14C]oleic acid, and muscle metabolites were analysed from needle biopsy samples.
2. Leg blood flow was not altered by ethanol. Alanine in arterial blood was reduced by approximately 25% after ethanol administration during exercise. A slight decrease in the concentration of NEFA in arterial plasma was observed after ethanol, associated with an increase in the fractional turnover of oleic acid, indicating an increased removal of NEFA from the plasma. The rate of uptake of NEFA in the leg was only slightly decreased.
3. The total glycogen depletion in leg muscle during exercise was not influenced by ethanol. The pattern of glycogen utilization in different muscle fibres was changed by ethanol and found to be dependent on the fibre composition of the respective subject. In the control experiments, but not after ethanol administration, a negative correlation was observed between glycogen utilization during exercise and the fraction of type I fibres.
4. It is concluded that ethanol administration during exercise (a) decreases leg uptake of NEFA due to a lower concentration of NEFA in plasma, although this lower uptake is compensated by an increased fractional oxidation, (b) does not influence total glycogen depletion in leg muscle, (c) changes the pattern of glycogen utilization in different muscle fibres, (d) influences only to a small extent the energy supply to working muscles, the most predominant isolated effect being on inhibition of the lactate release.
Intracellular Potassium and Steroidogenesis of Isolated Rat Adrenal Cells: Effect of Potassium Ions and Angiotensin II on Purified Zona Glomerulosa Cells
Authors: Mackie C. M. , Simpson E. R. , Mee M. S. R. , Tait S. A. S. , Tait J. F. 
Published: August 2015

1. A method involving centrifugation through phthalate ester oils is described for the rapid separation of isolated cells from suspending medium. Intracellular potassium concentrations and intracellular water space values for isolated adrenal zona glomerulosa and zona fasciculata cells are given.
2. The effects of angiotensin II and a high external potassium concentration (8·4 mmol/l) on intracellular potassium contents, intracellular water spaces and hence intracellular potassium concentrations of purified glomerulosa cells have been investigated. Corticosterone secretion was also measured. Previously reported results showing a significant increase in potassium content with high external potassium were confirmed. However, angiotensin II slightly, but significantly, decreased potassium content. No significant change in intracellular water space or intracellular potassium concentration was observed with either stimulus.
3. Both stimuli significantly increased corticosterone production. There was no correlation between the percentage increase in potassium content or concentration and the percentage increase in steroid output after stimulation with high external potassium.
4. It is concluded that angiotensin II does not stimulate steroidogenesis in adrenal glomerulosa cells by raising the intracellular potassium concentration. The small, but statistically insignificant, increase caused by high-potassium medium is unlikely to be causally linked to steroidogenesis.
Plasma Catecholamines and the Pressor Response to Sar1-Ala8-Angiotensin II in Man
Authors: McGrath B. P. , Ledingham J. G. G. , Benedict C. R. 
Published: August 2015

1. The initial blood pressure response to saralasin (Sar1-Ala8-angiotensin II) infusion was examined in 15 normal subjects, eight patients with untreated essential hypertension and 65 patients established on chronic haemodialysis (including six anephric patients), and related to measurements of plasma renin activity (PRA), angiotensin II, plasma catecholamines (noradrenaline and adrenaline), blood volume and extracellular fluid volume ([35S]sulphate space or exchangeable sodium).
2. A transient rise in arterial pressure, maximum after 5–6 min, occurred in all normal subjects, patients with essential hypertension and anephric patients, and in 41 of the 59 dialysis patients with kidneys.
3. In the normal subjects, saralasin infusion resulted in a significant rise in plasma noradrenaline (mean increase 360%, P < 0·02) without change in plasma adrenaline concentration. The change in noradrenaline was significantly related to the change in mean blood pressure (P < 0·05) and was similar to the response to 5 min of a 40° head-up tilt.
4. An increase in plasma noradrenaline also occurred in dialysis patients (P < 0·005) but the change in mean blood pressure with saralasin in this group was inversely related to PRA (P < 0·001) and angiotensin II (P < 0·001), directly related to blood volume (P < 0·001), but unrelated to the change in plasma noradrenaline.
5. The pressor response to saralasin may be mediated not only by angiotensin-like action on vascular receptors but also by an action on the central or peripheral autonomic nervous system.
The Treatment of Acute Intermittent Porphyria with Laevulose
Authors: Brodie M. J. , Moore M. R. , Thompson G. G. , Goldberg A. 
Published: August 2015

1. The activities of the enzymes of haem biosynthesis were studied in 23 patients with acute intermittent porphyria. The mitochondrial enzymes δ-aminolaevulinate synthase, coproporphyrinogen oxidase and ferrochelatase were measured in leucocytes and the cytosolic enzymes δ-aminolaevulinate dehydratase, porphobilinogen deaminase and uroporphyrinogen decarboxylase in erythrocytes.
2. Leucocyte δ-aminolaevulinate synthase activity was elevated (P < 0·001), with marked diminution of porphobilinogen deaminase activity (P < 0·001) and reduction in the activities of δ-aminolaevulinate dehydratase (P < 0·01) and uroporphyrinogen decarboxylase (P < 0·005).
3. A therapeutic regimen based on intravenous laevulose infusion was studied. In four patients in acute attack and one in remission laevulose treatment was associated with a fall in δ-aminolaevulinate synthase activity, a rise in porphobilinogen deaminase and uroporphyrinogen decarboxylase activities, and a fall in urinary porphyrin precursor excretion (P < 0·001). These studies provide a basis for the evaluation of the use of sugars in acute intermittent porphyria.
Effects of Renal Dopamine Receptor and β-Adrenoreceptor Blockade on Rises in Blood Angiotensin after Haemorrhage, Renal Ischaemia and Frusemide Diuresis in the Dog
Authors: Bell C. , Lang W. J. 
Published: August 2015

1. In chloralose-anaesthetized dogs, central venous and arterial angiotensin (AII) levels were monitored by blood-bathed bioassay during venous haemorrhage of 20 ml/kg, acute renal ischaemia induced by suprarenal aortic stenosis and frusemide-induced diuresis.
2. Blockade of intrarenal dopamine receptors with ergometrine reduced markedly the increments in arterial AII associated with haemorrhage or suprarenal aortic stenosis, but did not consistently affect the corresponding increments in venous AII.
3. Ergometrine or renal denervation did not affect the increases of blood AII associated with frusemide diuresis.
4. Blockade of β-adrenoreceptors with propranolol, by contrast, reduced blood AII increments associated with all three procedures.
5. It is suggested that renin release during moderate haemorrhage and acute suprarenal aortic stenosis is, in the dog, partly due to activation of intrarenal dopaminergic nerves.
6. The possibility is discussed that propranolol may depress renin release in the dog by an action other than that of blocking β-adrenoreceptors.
Motion of the Rib Cage and the Abdomen in Tetraplegic Patients
Authors: Mortola J. P. , Ambrogio G. Sant' 
Published: August 2015

1. We have studied the motion of the abdomen and the rib cage in patients with a transection of the lower cervical spinal cord during normal breathing both in the supine and sitting posture, and compared it with that of normal subjects.
2. In the supine posture the rib cage of a patient moves paradoxically inward, therefore his chest wall is deformed, which explains the high work of breathing.
3. During expiration, beside the recoil of the respiratory system, there is also the recoil of the deformed chest wall, toward its passive configuration, with an expansion of the rib cage above its resting position during the first part of expiration and an alteration of the expiratory flow profile.
4. In a sitting ‘relaxed’ posture the paradoxical inward motion disappears in the lower rib cage, and it is reduced but still present in the higher rib cage.
5. We conclude that contraction of the diaphragm constricts the ‘passive rib cage’, either directly through its insertions or indirectly through the reduction of intrathoracic pressure. In seated subjects the diaphragm causes some expansion of the rib cage at its lower level. Therefore the motion of the rib cage is not only related to the balance between the forces developed by the diaphragm and the intercostal muscles, but also to the diaphragm dome configuration, the geometry of the rib cage and the lung volume.
Elimination of Porcine Secretin in Pigs
Authors: Fahrenkrug J. , de Muckadell O. B. Schaffalitzky , Holst J. J. 
Published: August 2015

1. The elimination of immunoreactive secretin was studied in anaesthetized pigs by using constant infusions of pure natural porcine secretin.
2. The mean metabolic clearance rate was 15·4 ml min—1 kg—1, and was independent of the level at which it was determined. The mean distribution space was 64·4 ml/kg. The half-life of secretin after termination of the infusion averaged 2·6 min.
3. During intravenous infusion of secretin in a dose of 27·8 pmol h—1 kg—1 the renal extraction was 52%. Exclusion of the kidneys increased plasma secretin concentration from 26·5 pmol/l to 47·3 pmol/l and increased the half-life to 4·4 min.
4. Exclusion of the liver during infusion of secretin in a dose of 27·8 pmol h—1 kg—1 resulted in an increment in plasma secretin concentration of 7·8 pmol/l and an increase of the half-life to 3·6 min.
5. A gradient of endogenous secretin across the liver was present but no arteriovenous difference was found across the foreleg.
6. Incubation of secretin with whole blood or serum for 20 min at 37°C did not result in any degradation of secretin.
The Metabolic Response to Galactose as a Measure of Hepatic Glucose Release in Man
Authors: Royle G. , Kettlewell M. G. W. , Ilic Vera , Williamson D. H. 
Published: August 2015

1. Galactose utilization after intravenous injection was measured in fed and fasted man together with changes in blood glucose, lactate and insulin.
2. Feeding did not alter blood galactose half-life.
3. The mean increases in blood glucose and lactate were greater in the fasted subjects but their concentrations reached similar values in both fed and fasted states.
4. Plasma insulin increased after galactose in the fasted state, but there was no change in the fed state, indicating that galactose is not insulinogenic.
5. After an intravenous galactose load in the fed state insulin appears to inhibit hepatic glucose release.
6. An intravenous galactose test might be a useful measure of hepatic glucose release under different physiological and pathological conditions.
Bartter's Syndrome: Contrasting Patterns of Prostaglandin Excretion in Children and Adults
Authors: Dray F. 
Published: August 2015

1. The daily urine excretion has been studied of prostaglandins (PG) E2 and F2α, as measured by radioimmunoassay, in eight children and seven adults with Bartter's syndrome.
2. Excretion of both PGE2 and PGF2α was significantly higher in the patients with Bartter's syndrome than in 17 normal children.
3. Twelve normal adults excreted significantly more PGE2 and PGF2α than did the normal children. In contrast, adults with Bartter's syndrome did not show an increase in prostaglandin excretion.
The Relation between Plasma Androstenedione, Plasma Oestrone and Androstenedione to Oestrone Conversion Rates in Postmenopausal Women with and without Fractures
Authors: Pelc B. , Marshall D. H. , Guha P. , Khan M. Y. , Nordin B. E. C. 
Published: August 2015

1. Plasma androstenedione, plasma oestrone and the conversion of plasma androstenedione into oestrone were measured in 19 post-menopausal women without fractures (six of them oophorectomized) and 18 with vertebral or femoral neck fractures (four of them oophorectomized).
2. In the series as a whole, the main determinant of the plasma oestrone level was the plasma androstenedione concentration. Only in the small oophorectomized group did the variation in conversion rate make a significant contribution to the variation in plasma oestrone.
3. The conversion rates were not different as between non-fracture and fracture cases but the mean plasma androstenedione and oestrone concentrations were lower (though not significantly) in the latter.
Effect of Cyclo-Alkyl Lactamimides upon Human Pepsins and Pepsinogens
Authors: Roberts N. B. , Taylor W. H. 
Published: August 2015

1. Eight cyclo-alkyl lactamimides have been investigated for potential inhibitory action upon the pepsins and pepsinogens.
2. Human pepsins 1, 3 and 5 and swine pepsin were inhibited only slightly.
3. Human and swine pepsinogens were inactivated progressively by lactamimides as the number of methylene groups in the nitrogen-containing ring increased. The most potent in activator studied was N-(cis-2-phenylcyclopentyl)azacyclotridecan-2-imine hydrochloride.
4. Substitution of benzyl and tertiary butyl groups in the N-containing ring increased the pepsinogen-inactivating property of the cyclo-alkyl lactamimides.
5. N-(cis-2-Phenylcyclopentyl)azacyclotridecan-2-imine hydrochloride may be of potential importance as a therapeutic agent in peptic ulcer, and modifications to the molecule which might increase its pepsinogen-inactivating ability are suggested.
The Role of Sodium Depletion in Hydrochlorothiazide-Induced Antidiuresis in Brattleboro Rats with Diabetes Insipidus
Authors: Shirley D. G. , Walter S. J. , Laycock J. F. 
Published: August 2015

1. The mechanism of the antidiuretic effect of hydrochlorothiazide in diabetes insipidus was studied in anaesthetized Brattleboro rats with the hereditary hypothalamic form of the disease.
2. The antidiuresis caused by acute administration of hydrochlorothiazide followed an increase in sodium excretion and was associated with a significant fall in the plasma sodium concentration. There were concomitant falls in effective renal plasma flow and glomerular filtration rate.
3. When sodium depletion was prevented by adjusting the infusion of sodium chloride, the falls in plasma sodium concentration, effective renal plasma flow and glomerular filtration rate were abolished. Under these circumstances there was an increase in urine volume, which suggests that hydrochlorothiazide may inhibit fractional fluid reabsorption in the proximal convoluted tubule.
4. The results indicate that the antidiuresis caused by hydrochlorothiazide in diabetes insipidus results, at least in part, from falls in effective renal plasma flow and glomerular filtration rate. These in turn seem to be entirely secondary to the drug-induced sodium depletion.
The Metabolism of Tartrate in Man and the Rat
Authors: Chadwick V. S. , Vince A. , Killingley M. , Wrong O. M. 
Published: August 2015

1. Sodium tartrate labelled with 14C was given orally and parenterally to man and rats, and by direct injection into the caecum in rats. From the differences in urinary excretion after oral and parenteral administration intestinal absorption of tartrate was calculated as 18% of the dose in man and 81% in rats. Urinary tartrate was equivalent to 14% of the dose in man and 70% in rats, the difference between absorption and urinary excretion representing metabolism in body tissues.
2. Both man and the rat excreted part of the 14C as respiratory carbon dioxide. This occurred to a small extent after parenteral injection, suggesting metabolism of tartrate by body tissues, but was greater after oral or intracaecal administration, indicating that the main site of tartrate metabolism is the intestine.
3. Several genera of intestinal bacteria were shown to liberate [14C]carbon dioxide from labelled tartrate, and in a faecal incubation system l-tartrate, the natural isomer, was metabolized five times as rapidly as d-tartrate.
4. Oral sodium l-tartrate, 1·5 mmol day—1 kg—1, was given to two subjects and was shown to alkalinize the urine like sodium salts of other organic acids which are metabolized in the body. The reduction in renal hydrogen ion excretion showed that an average of 84% of the dose was metabolized.
5. Only 5% of labelled tartrate given by mouth appeared in faeces, and pharmacological doses of unlabelled l-tartrate had little or no aperient effect.
6. No evidence of toxicity of l-tartrate was encountered.
The Interpretation of Different Measurements of Airways Obstruction in the Presence of Lung Volume Changes in Bronchial Asthma
Authors: Saunders K. B. , Rudolf M. 
Published: August 2015

1. We measured changes in peak expiratory flow rate (PEFR), forced expiratory volume in 1 s (FEV1·0), airways resistance (Raw), specific conductance (sGaw), residual volume (RV), functional residual capacity (FRC) and total lung capacity (TLC) in 44 patients with asthma.
2. When asthma was induced by exercise in five patients there were large changes in volumes, but these did not obscure changes in PEFR, which adequately defined the time course of the response.
3. In 70 comparisons before and after inhalation of bronchodilator drug in 33 asthmatic subjects, the responses were classified by the size of the change in lung volumes, which showed a concordant improvement, or no change, in 61 comparisons. Despite these lung volume changes, measurement of both PEFR and FEV1·0, would have detected a bronchodilator response in all but two cases.
4. In 81 comparisons in 23 subjects over time intervals varying from 1 day to 11 months, lung volumes changed in concordance with PEFR and FEV1·0 in 59. In eight of these comparisons, measurement of lung volumes would have altered our interpretation of the changes in PEFR and FEV1·0.
5. In the same 81 comparisons changes in airways resistance were concordant with changes in PEFR and FEV1·0 on 44 occasions, with minor discordant changes in 19. We could not explain the remaining 18 cases showing major discordance between these two types of measurement of airway calibre.
6. We conclude that both FEV1·0, and PEFR should be used for detection of a bronchodilator response, and that measurement of lung volumes will rarely contribute to the interpretation. Over longer periods, lung volumes should be measured if possible. We found no practical use for routine measurement of airways resistance in patients with asthma.
Comparison of Human Myofibrillar Protein Catabolic Rate Derived from 3-Methylhistidine Excretion with Synthetic Rate from Muscle Biopsies during l-[α-15N]Lysine Infusion
Authors: McKeran R. O. , Halliday D. , Purkiss P. 
Published: August 2015

1. Urine was collected in five healthy men over 10–14 days, with fasting blood samples on days 1, 5 and 10, whilst they consumed a standard creatine-free diet, which was quantitatively related to their body surface area.
2. The urinary excretion of 3-methylhistidine fell to a plateau by day 5 in all subjects. Myofibrillar protein catabolic rate calculated from the mean value of 3-methylhistidine excretion from day 5 to day 10 averaged 1·21 g day−1 kg−1 body weight. The average turnover of muscle myofibrillar protein was calculated to be 2·16%/day.
3. From a previous study using continuous intravenous infusion of l-[α-15N]lysine with serial muscle biopsies on the same subjects, the mean myofibrillar protein synthetic rate was calculated to be 0·82 g day−1 kg−1 body weight, and the mean turnover rate was 1·47%/day of total muscle myofibrillar protein.
4. The estimations of myofibrillar protein turnover rate derived from the two methods are compared and the differences discussed.