bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some Aspects of Sodium Movement across Porcine Aortic Walls in Vitro
Authors: Edwards I. R. 
Published: August 2015

1. Sodium movement across the porcine aortic arch in vitro is greater from the intimal to the medial surface than in the reverse direction.
2. A short-circuit current can be measured across the aortic arch and the calculated energy is greater than the energy required to support the net outward sodium movement, suggesting the possibility of active transport of other ions.
3. Net sodium movement is not significantly altered by an adverse gradient on the outside (medial side) but is reduced by a gradient in the opposite direction.
4. Sodium retention within the tissue is increased by a gradient on the medial side.
5. The movement of [14C]inulin is greater from the medial to the intimal surface, suggesting greater porosity on the medial side. A slight rise in both total tissue fluid and extracellular fluid occurred when the sodium concentration on the medial side of the preparation was increased. This did not occur with the sodium concentration increased on the intimal side. The changes were only significant statistically for total tissue fluid.
6. The short-circuit current can be enhanced by adrenaline and reduced by a variety of β-adrenoreceptor-blocking agents.
7. It appears that aortic tissue can actively transport sodium and it is suggested that this mechanism could play a part in blood pressure control.
Reflex Control of Renin Release in Essential Hypertension
Authors: Mancia G. , Leonetti G. , Terzoli Laura , Zanchetti A. 
Published: August 2015

1. The reflex control of renin release was studied in subjects with essential hypertension by comparing the effects of a variable-pressure neck chamber and head-up tilting.
2. Increase in carotid sinus transmural pressure (obtained by reducing tissue pressure outside the carotid sinus by 34 ± 3 mmHg) decreased mean arterial pressure by 16 ± 2 mmHg, but did not reduce significantly the renal venous—arterial difference in plasma renin activity. Likewise decrease in carotid sinus transmural pressure (obtained by increasing tissue pressure outside the carotid sinus by 39 ± 2 mmHg) increased mean arterial pressure by 14 ± 3 mmHg, but caused only a very slight increase in the renal venous—arterial difference in plasma renin activity.
3. Passive tilting reduced mean arterial pressure by 9 ± 1 mmHg. In this circumstance the renal venous—arterial difference in plasma renin activity increased significantly and markedly.
4. It is concluded that in essential hypertension the carotid sinus baroreceptors, though active in blood pressure control, do not exert a major influence on renin release. In these patients reflex increase of renin during tilting is apparently mediated through other receptors than those in the carotid sinuses.
Lack of a Role for the Renal Nerves in Renal Sodium Reabsorption in Conscious Dogs
Authors: Lifschitz M. D. 
Published: August 2015

1. Studies in anaesthetized animals suggest that the renal nerves have a role in the regulation of sodium excretion. Urinary sodium excretion decreases when the renal nerves are stimulated and increases after renal denervation or ganglionic blockade. In order to define the role of the renal nerves in the regulation of urinary sodium excretion in awake animals, dogs were prepared with one kidney denervated and the other intact and the bladder split so that urine could be collected from each kidney. Denervation was confirmed by kidney noradrenaline analysis (1·72 ± 0·29 vs 0·18 ± 0·12 nmol/g).
2. These dogs were studied awake with one of two protocols on each of two separate days. In protocol VH, volume expansion (5% body weight) was followed by haemorrhage of 2% body weight. Fractional sodium excretion fell from 4·7 ± 0·5 to 1·1 ± 0·2% on the denervated side and from 5·6 ± 0·6 to 1·4 ± 0·3% on the intact side. Inulin and p-aminohippurate clearance fell similarly on both sides.
3. In protocol HV, haemorrhage of 2% body weight was followed by blood replacement and volume expansion of 5% body weight. In this second protocol fractional sodium excretion during haemorrhage was 0·23 ± 0·07 and 0·24 ± 0·09% for denervated and intact kidneys respectively and increased to 2·04 ± 0·32 and 2·78 ± 0·60 after volume expansion.
4. In both protocols the denervated kidney was able to reabsorb sodium as well as the innervated kidney during haemorrhage and was able to increase fractional sodium excretion as well as the denervated kidney during volume expansion. These results suggest that the renal nerves do not have a significant role in the regulation of sodium excretion in conscious animals.
Effects of Airway Anaesthesia on the Ability to Detect Added Inspiratory Resistive Loads
Authors: Chaudhary B. A. , Burki N. K. 
Published: August 2015

1. The effects of airway anaesthesia on the ability to detect added inspiratory resistive loads were studied in normal subjects. A 4% solution of lignocaine hydrochloride was used for anaesthesia of the airways.
2. After anaesthesia of the mouth and upper always to the level of the vocal cords there was a significant deterioration in the detection ability expressed in terms of the absolute added resistance (ΔR), with a concomitant increase in pulmonary resistance (Rint.). However, there was no significant change in the detection ability expressed in terms of the ratio of ΔR to the sum of Rint. and the minimal resistance of the apparatus (ΔR/R0).
3. After combined anaesthesia of the upper and lower airways there was no significant change in pulmonary resistance or in the detection ability expressed either as ΔR or as ΔR/R0.
4. We conclude that, in normal subjects, the main site of detection of added inspiratory resistive loads does not lie in the upper or lower airways. Our results and those of previous studies suggest that the diaphragm is the most likely site of detection of added resistive loads.
Induction of Lysinuria in the Rat by Two Para-Substituted Guanidinophenylalanines
Authors: Owens C. W. I. 
Published: August 2015

1. p-Guanidino- and p-guanidinomethyl-phenylalanine increase the renal excretion of lysine especially and, to some extent, cystine in the phenylalanine-loaded rat. The methyl derivative is the more effective.
2. The lysinuria is dose-dependent, reversible, pronounced when the intravenous infusion of analogue exceeds 10 μmol min−1 kg−1 and does not appear to be secondary to changes in urine flow or sodium excretion.
3. A mechanism for induced basic aminoaciduria conditions is suggested.
Intestinal Absorption and Tissue Retention of Cadmium and Calcium in Normal Adult Rats and Rats Given an Active Metabolite of Vitamin D (1,25-Dihydroxycholecalciferol)
Authors: Lorentzon R. , Larsson S.-E. 
Published: August 2015

1. Nine-months-old male rats were divided into a normal control group and one experimental group which received eight daily intraperitoneal injections of 15 pmol of 1,25-dihydroxycholecalciferol/100 g body weight. After 5 days, 20 μCi of 109CdCl2 or 20 μCi of 45CaCl2 was administered by stomach tube. The intestinal absorption and tissue retention of the radioisotopes were analysed during the next 3 days, the animals being kept in metabolic cages.
2. The administration of 1,25-dihydroxycholecalciferol caused significantly increased net absorption of intestinal calcium, hypercalcaemia and increased incorporation of calcium into bone. In comparison, there was no significant effect on the intestinal absorption of trace doses of cadmium or upon the accumulation of cadmium in the liver and kidneys.
Validation of ‘Transit Renography’ for the Determination of the Intrarenal Distribution of Plasma Flow: Comparison with the Microsphere Method in the Anaesthetized Rabbit and Pig
Authors: Wilkinson S. P. , Bernardi M. , Pearce P. C. , Britton K. E. , Brown N. J. G. , Poston L. , Clarke M. , Jenner R. , Williams Roger 
Published: August 2015

1. The spectrum of transit times of sodium o-iodohippurate (Hippuran) through the kidney can be derived from an 131I- (or 123I-) labelled Hippuran renogram by deconvolution. In the rabbit and pig, as has previously been shown in man, the frequency distribution curve for the transit times was bimodal. Since the transit time is likely to be proportional to the nephron length, the area of the first mode is likely to represent plasma flow to the shorter outer cortical nephrons whereas the delayed mode represents flow to the long juxtamedullary nephrons.
2. This interpretation was tested by simultaneously comparing renography with the microsphere method of measuring intrarenal plasma flow distribution in 12 rabbits and two pigs with a variety of anaesthetics. A close agreement was found between both methods for the percentage of plasma flow distributed to the outer cortical nephrons, thus supporting the use of ‘transit renography’ to determine the intrarenal distribution of plasma flow.
A Survey of Salivary Kallikrein and Amylase in a Population of Schoolgirls, throughout the Menstrual Cycle
Authors: Bhoola K. D. , Matthews R. W. , Roberts Fiona 
Published: August 2015

1. The values for kallikrein, amylase and protein were determined in samples of saliva obtained from 220 girls aged 14–18 years.
2. The concentrations of protein and amylase and kallikrein activities (per ml of saliva) were considerably more variable in samples taken in the morning than those in the afternoon.
3. The median amylase activity was about two and a half times greater in the morning than that in the afternoon. No such differences were seen in the median values for protein or kallikrein.
4. Examination of the values for salivary kallikrein during the menstrual cycle showed that there was significantly greater activity during days 29–32 and 1–4 than during the rest of the cycle. This pattern was most marked in the morning values of kallikrein but not apparent either in the morning or in the afternoon values of protein or amylase.
Plasma Adrenaline and Noradrenaline in Essential Hypertension and after Long-Term Treatment with β-Adrenoreceptor-Blocking Agents
Authors: Franco-Morselli R. , Baudouin-Legros M. , Meyer P. 
Published: August 2015

1. Plasma adrenaline and noradrenaline were measured in supine and upright positions in 27 essential hypertensive patients and in 12 age-matched control subjects.
2. Plasma adrenaline was markedly increased in a large proportion of patients, compared with control subjects, either in supine or in upright positions, whereas no significant differences were found in plasma noradrenaline.
3. Six hypertensive patients were chronically treated with β-adrenoreceptor-blocking agents (five with propranolol and one with pindolol). Plasma noradrenaline was not significantly changed in the supine position but was markedly increased on standing in four out of six patients. Plasma adrenaline was decreased in five out of six patients either in supine or upright positions.
4. These findings support the view that the adrenergic system participates in the mechanism of essential hypertension.
Redistribution of Regional Blood Flow after Administration of Saralasin in Salt-Depleted Dogs
Authors: Liang Chang-Seng , Gavras Haralambos , Brunner H. R. 
Published: August 2015

1. Salt depletion was produced in five dogs by a low salt diet and daily administration of frusemide for 5 days; a control group of five dogs was placed on the same diet, to which 2·5 g of sodium chloride was added.
2. Saralasin infusion (0·5 μg min−1 kg−1) reduced mean aortic blood pressure and total peripheral vascular resistance and increased cardiac output in salt-depleted dogs, but did not affect the heart rate and left ventricular dP/dt.
3. Saralasin infusion increased mean aortic blood pressure slightly in normal dogs; other systemic haemodynamic parameters did not change significantly.
4. Saralasin decreased hepatic arterial flow in both normal and salt-depleted dogs, but increased blood flow to left ventricle and kidneys only in salt-depleted dogs.
5. These results suggest that saralasin exerts a partial agonist effect in normal dogs to increase arterial blood pressure, but causes a depressor response during salt depletion because it reverses the vasoconstrictor effect of angiotensin II, particularly on the renal and coronary circulations.
Haemodynamic Effects of a Calcium Antagonistic Agent (Nifedipine) in Hypertension: Therapeutic Implications
Authors: Bartorelli C. , Magrini F. , Moruzzi P. , Olivari M. T. , Polese A. , Fiorentini C. , Guazzi M. 
Published: August 2015

1. In 27 severe primary hypertensive patients nifedipine (10 mg), administered orally, induced prompt (–21% of control at 30 min) and persistent (–17% at 120 min) fall of mean arterial pressure mediated through reduction of peripheral vascular resistance with rise of cardiac output.
2. The sublingual route (nine cases) showed more rapid onset of action and equal antihypertensive effectiveness.
3. In five patients with hypertensive crisis and acute left ventricular failure, the drug strikingly reduced systemic and pulmonary arterial pressures and relieved pulmonary oedema.
4. Prompt efficacy, ease of administration, absence of important side effects indicate that nifedipine may be a useful therapeutic agent in severe hypertension and in critical conditions that require rapid lowering of blood pressure.
Arousal and the Circadian Rhythm of Blood Pressure
Authors: Floras J. S. , Jones J. V. , Johnston J. A. , Brooks D. E. , Hassan M. O. , Sleight P. 
Published: August 2015

1. We have recorded ambulant intra-arterial blood pressure in five normo- and 14 hyper-tensive subjects over 24 h, particular attention being paid to the timing of arousal.
2. The data were edited beat-by-beat before storing systolic, diastolic, and mean blood pressure ± sd for every 2 min period on a computer file.
3. When pooled hourly mean data are plotted there is a rise of 52·9 mmHg systolic and 22·3 mmHg diastolic pressure from 03.00 hours to 11.00 hours in the 14 hypertensive subjects.
4. When the data are plotted in 20 min periods for the hours before and after arousal it is clear that the major rise in pressure occurs abruptly at that time. The 2 h period before arousal shows only a small rise in pressure, i.e. 6·9 mmHg systolic and 2·9 mmHg diastolic.
5. It is suggested that the apparent rapid early morning rise of blood pressure is an artifact of the method of analysis.
Relaxation Rate of Constituent Muscle-Fibre Types in Human Quadriceps
Authors: Wiles C. M. , Young A. , Jones D. A. , Edwards R. H. T. 
Published: August 2015

1. Muscle fibres may be subdivided into type I (with slow-twitch contractile properties) and type II (fast-twitch) depending on their myosin adenosine triphosphatase activity. In voluntary isometric contractions type I fibres are utilized at low forces (&lt;20% of maximum) whereas type II fibres are recruited in addition at high forces. This physiological recruitment order has enabled us to measure the relaxation rate of type I and II fibres in vivo in normal human subjects.
2. Relaxation rate was measured in 16 subjects from low (10% of maximum) and maximum isometric quadriceps contractions and the muscle-fibre type composition determined from needle-biopsy specimens in 10 subjects. The relaxation rate of type II fibres was calculated to be twice as fast as that of type I.
3. It was not possible to estimate, from studies in 33 quadriceps muscles (25 normal subjects), the contribution of type II fibres to overall fibre area from the relaxation rate as determined from electrically stimulated isometric contractions.
Erythropoiesis, Iron Stores and Tissue Iron Exchange in Man
Authors: Cavill I. , Ricketts C. , Jacobs A. 
Published: August 2015

1. The exchange of iron between plasma and erythroid and non-erythroid tissues was measured in 14 normal subjects, 17 iron-deficient patients, nine patients with primary idiopathic haemochromatosis and in 13 patients with haemolytic disorders.
2. The two main factors determining tissue iron turnover were shown to be the level of iron stores and the erythropoietic activity of the bone marrow.
Heart-Rate Response to Sustained Hand Grip: Comparison of the Effects of Cardiac Autonomic Blockade and Diabetic Autonomic Neuropathy
Authors: Hume L. , Ewing D. J. , Campbell I. W. , Reuben S. R. , Clarke B. F. 
Published: August 2015

1. The heart-rate response during sustained hand grip was studied in four normal subjects before and after intravenous atropine, propranolol and combined cardiac autonomic blockade with both drugs. The results suggest that the increase in heart rate during the first 30 s is due to parasympathetic withdrawal, whereas the further increase between 30 s and 180 s is probably mediated by a combination of parasympathetic withdrawal and sympathetic stimulation.
2. The increases in heart rate during each minute of sustained hand grip were compared in 26 normal subjects, 37 diabetic subjects without and 24 diabetic subjects with proven autonomic neuropathy. In the diabetic subjects with autonomic neuropathy the increase in heart rate during the first minute was impaired, whereas the increases during the second and third minutes were similar in all three groups.
3. The initial increase in heart rate over the first 30 s of hand grip and the later increase between 30 s and 180 s were compared in nine normal subjects, ten diabetic subjects without and six diabetic subjects with autonomic neuropathy. The increase during the first 30 s was impaired in the diabetic subjects with autonomic neuropathy, whereas the later phase of the response was similar in all three groups.
4. It is concluded that impairment of the heart-rate response to sustained hand grip in diabetic autonomic neuropathy is mainly due to impairment of the early parasympathetic phase, but that the presence of cardiac sympathetic damage can also be detected.
Plasma Level and Renal Clearance of Oxalate in Normal Subjects and in Patients with Primary Hyperoxaluria or Chronic Renal Failure or Both
Authors: Constable A. R. , Joekes A. M. , Kasidas G. P. , O'regan P. , Rose G. A. 
Published: August 2015

1. Plasma oxalate has been measured by a radioisotopic method applicable to all concentrations of plasma oxalate and renal function, and also by an enzymatic method which was only applicable to raised concentrations of plasma oxalate.
2. Where the two methods could be applied simultaneously, the agreement between them was good.
3. Plasma oxalate was 86% ultrafiltrable at concentrations of up to 44 μmol/l.
4. Oxalate clearance and the exchangeable oxalate pool were also measured. The ratio of oxalate clearance to creatinine clearance was greater than unity in most normal subjects and patients.
5. These methods were used in normal subjects and in patients with primary hyperoxaluria and/or chronic renal failure. A raised plasma oxalate concentration was found in both conditions. Chronic renal failure is probably the most common cause of a raised plasma oxalate.
Arterial Distensibility in Normal and Hypertensive Man
Authors: Gribbin B. , Pickering T. G. , Sleight P. 
Published: August 2015

1. The pulse-wave velocity along the brachial radial artery was measured in 38 subjects and volume distensibility values were calculated.
2. Measurements made at each subject's resting blood pressure showed that those with high blood pressure had higher pulse-wave velocity values and hence less distensible arteries.
3. An acute rise in arterial distending pressure was accompanied by a rise in pulse-wave velocity.
4. When pulse-wave velocity was remeasured in all subjects at identical arterial distending pressures, no difference was found between hypertensive and normal subjects.
5. It appears that poor distensibility of large arteries in hypertensive subjects is a consequence of the elevated distending pressures and not due to irreversible structural changes in the arterial wall.
Effects of Aprotinin on Renal Function and Urinary Prostaglandin Excretion in Conscious Rats after Acute Salt Loading
Authors: Kramer H. J. , Moch T. , Von Sicherer L. , Düsing R. 
Published: August 2015

1. Aprotinin, a potent kallikrein inhibitor, was given to conscious rats with and without expansion of the extracellular fluid volume with isotonic saline.
2. In noa-expanded rats aprotinin had no effect on arterial pressure, glomerular filtration rate (GFR), hippuran clearance, urinary flow rate, absolute sodium and potassium excretion or free-water clearance.
3. In volume-expanded rats aprotinin significantly reduced GFR, hippuran clearance, urine volume (V) UNaV, UKV and Cwater/GFR without effect on systemic arterial pressure.
4. Urinary immunoreactive prostaglandin E2 excretion significantly increased during the expansion phase but returned to below the control range during stable extracellular fluid volume expansion.
5. Aprotinin significantly suppressed urinary immunoreactive prostaglandin E2 excretion in non-expanded rats and in volume-expanded rats during the expansion phase, but not during stable expansion.
6. The results suggest that the kallikrein-kinin system may contribute to changes in renal function during extracellular volume expansion. This action may not necessarily be associated with changes in renal prostaglandin E2 activity.
The Relationships between Plasma Substrates and Hormones and the Severity of Injury in 277 Recently Injured Patients
Authors: Stoner H. B. , Frayn K. N. , Barton R. N. , Threlfall C. J. , Little R. A. 
Published: August 2015

1. The plasma concentrations of glucose, lactate, amino acids, non-esterified fatty acids, glycerol, ketone bodies, ethanol, cortisol and insulin were measured in patients within a few hours of injury and before treatment. The severity of the injuries was assessed by the Injury Severity Score (ISS) method.
2. Plasma lactate and glucose concentrations both rose significantly with increasing ISS.
3. The concentrations of non-esterified fatty acids and glycerol were greater after moderate (ISS 7–12) than after minor (ISS 1–6) injuries. The glycerol concentrations were no higher and the non-esterified fatty acid concentrations were lower after severe (ISS &gt; 12) than after moderate injuries. The concentrations of total ketone bodies tended to follow those of non-esterified fatty acids and there was a highly significant correlation between them.
4. The total concentration of amino acids was not affected by the severity of injury and there were no systematic changes in the concentrations of individual ones.
5. Plasma insulin concentrations were very variable and not related to severity. A weak correlation with the plasma glucose concentration seen after minor and moderate injuries was lost in the severely injured.
6. The plasma cortisol concentration was positively related to ISS up to ISS 12 but negatively so in the severely injured.
7. Factors such as age, sex and time after last meal were investigated. The most important factor modifying the response was intake of ethanol, which reduced the plasma concentrations of glucose, non-esterified fatty acids and alanine and raised that of lactate as well as the [β-hydroxybutyrate]/[acetoacetate] ratio.
Subcellular Fractionation Studies of the Intestinal Mucosa in Congenital Sucrase—Isomaltase Deficiency
Authors: Cooper B. T. , Candy D. C. A. , Harries J. T. , Peters T. J. 
Published: August 2015

1. Jejunal biopsy specimens from three children with congenital sucrase—isomaltase deficiency were assayed for disaccharidase activity and were subjected to analytical subcellular fractionation with enzymic microanalysis.
2. By use of the highly sensitive fluorigenic modification of the disaccharidase assay, brush-border sucrase and isomaltase activities were depressed but nevertheless detectable in each child.
3. Apart from the expected decrease in brush-border α-glucosidase activity, the other enterocyte marker-enzyme activities were normal.
4. There were no abnormalities in the enterocytes of any child on analytical subcellular fractionation or on electron microscopy.