bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eel calcitonin suppresses plasma human calcitonin levels in medullary carcinoma of the thyroid
Authors: Morimoto S. , Miyauchi A. , Fukuo K. , Imanaka S. , Yamamoto H. , Tsuchiya H. , Koh E. , Yukawa S. , Onishi T. , Avioli L. V. , Kumahara Y. 
Published: August 2015

1. The effects of synthetic [Asu1,7]-eel calcitonin (0.5 MRC unit/kg body weight intravenously for 30 min) on circulating levels of human calcitonin, calcium and gastrin were investigated in five patients with medullary carcinoma of the thyroid.
2. Blood samples were obtained before and 15, 30, 60, 90, 120 and 180 min after commencement of infusion of [Asu1,7]-eel calcitonin. Plasma levels of human calcitonin were measured by radioimmunoassay. Cross-reactivity with [Asu1,7]-eel calcitonin in this assay was negligible.
3. On infusion of [Asu1,7]-eel calcitonin, the mean plasma level of human calcitonin decreased significantly to 71.0 ± 8.7% of the basal level (mean ± sem, P &lt; 0.05) after 30 min and 68.4 ± 25.4% of the basal level (P &lt; 0.05) after 60 min. The serum calcium level also decreased significantly, but lagged behind the decrease of human calcitonin, being 95.1 ± 0.7% of the basal level (P &lt; 0.01) at 120 min and 94.8 ± 0.6% of the basal level (P &lt; 0.02) at 180 min. The mean plasma gastrin level did not change significantly on infusion of [Asu1,7]-eel calcitonin.
4. In pooled data for all times, the percentage change in human calcitonin was not significantly correlated with either the percentage change in calcium (r = −0.25, P &gt; 0.1) or the percentage change in gastrin (r = −0.3 8, P &gt; 0.1).
5. These data suggested that [Asu1,7]-eel calcitonin suppressed calcitonin secretion in patients with medullary carcinoma of the thyroid. The mechanism of its effect is unknown.
Human calcitonin gene related peptide: a potent endogenous vasodilator in man
Authors: Struthers A. D. , Brown M. J. , Macdonald D. W. R. , Beacham J. L. , Stevenson J. C. , Morris H. R. , Macintyre I. 
Published: August 2015

1. In addition to calcitonin and katacalcin, it is now known that the human calcitonin gene encodes a novel peptide called calcitonin gene related peptide (CGRP). In experimental animals, CGRP produces vasodilatation and complex changes in plasma calcium.
2. We have now assessed its biological activity in man by infusing human CGRP (hCGRP) into six normal volunteers. hCGRP (545 pmol/min) caused the diastolic pressure to fall from 64 ± 5 to 55 ± 7mmHg (P &lt; 0.05), the heart rate to increase from 61 ± 7 to 87 ± 5 beats/min (P &lt; 0.05) and the skin temperature to increase from 33.7 ± 0.9 to 34.9 ± 0.5°C. Plasma noradrenaline increased from 481 ± 126 to 835 ± 65 pg/ml (P &lt; 0.05) and plasma adrenaline from 57 ± 17 to 82 ± 12 pg/ml (P &lt; 0.05). There were no significant changes in the albumin-corrected plasma calcium.
3. hCGRP is thus a potent endogenous vasodilator in man and is in fact more potent than any other known vasodilator. Together with the observations that CGRP circulates in normal subjects at relatively high concentration (approximately 25 pmol/l) and that CGRP is present in perivascular nerves, this study suggests a possible role for CGRP in controlling peripheral vascular tone in man.
Effects of verapamil alone and with captopril on blood pressure and bilateral renal function in Goldblatt hypertensive rats
Authors: Huang Wann-Chu 
Published: August 2015

1. The effects of verapamil infusion alone and superimposed with captopril on arterial pressure and bilateral renal function were evaluated in 21 two-kidney, one-clip Goldblatt hypertensive rats and in 13 control rats.
2. Verapamil significantly decreased arterial pressure of both hypertensive and control rats. Addition of captopril further reduced arterial pressure in hypertensive rats only.
3. There were significant increases in glomerular filtration rate (GFR), urine flow and absolute and fractional excretory rates of sodium and potassium in the non-clipped kidney. In contrast, these renal indices decreased in the clipped kidney. Superimposed captopril during verapamil infusion did not significantly change function of the non-clipped kidney but further depressed function of the clipped kidney.
4. In control rats, no significant change in GFR occurred in response to drugs. Renal excretion of water and sodium, but not potassium, increased after verapamil. However, the diuresis and natriuresis were less pronounced than those seen in the non-clipped kidney of hypertensive rats.
5. There was a proportionate increase in osmolar clearance and free water reabsorption rate in the non-clipped kidney and the normal kidney. The linear relationship did not change after verapamil infusion.
6. The results suggest that verapamil enhances the excretory function of the non-clipped kidney of Goldblatt hypertensive rats via increased GFR and decreased tubular reabsorption in the proximal and/or distal tubules despite its hypotensive action.
Effect of indirect heating on the postural control of skin blood flow in the human foot
Authors: Hassan A. A. K. , Rayman G. , Tooke J. E. 
Published: August 2015

1. It has been shown in previous studies that skin blood flow in the human foot falls when the extremity is placed below heart level, owing to an increase in precapillary resistance that is probably mediated by a local sympathetic axon reflex or a myogenic response.
2. In order to clarify the influence of the central thermoregulatory mechanisms on this local postural vasoconstrictor response, 12 normal male subjects were studied under standardized conditions, at rest and during heating of the trunk with an electric blanket.
3. Skin blood flow was measured before and during body heating using laser Doppler flowmetry with the foot maintained at heart level and placed passively 50 cm below the heart.
4. Skin blood flow and skin temperature were determined at two sites: (a) the plantar surface of the big toe, an area with a relatively large number of arteriovenous anastomoses, and (b) the dorsum of the same foot, where these anastomoses are few or absent.
5. When the foot was placed in the dependent position, skin blood flow recorded in the dorsum of the foot during indirect heating fell to a level similar to that achieved before heating. In contrast, indirect heating greatly diminished the postural fall in skin blood flow recorded in the plantar surface of the big toe.
6. In conclusion, the partial release of sympathetic vasoconstrictor tone associated with indirect heating appears to over-ride the local postural control of cutaneous vascular tone in areas where arteriovenous anastomoses are relatively numerous.
Alterations of intestinal membrane-bound enzymes in three types of hypertensive rats
Authors: Gilles-Baillien M. , Carlier P. G. , Rorive G. L. 
Published: August 2015

1. Alkaline phosphatase, sucrase, Na+, K+-ATPase and Mg2+-ATPase specific activities of crude membrane fractions, prepared from duodenal, jejunal, ileal and colonic mucosa, have been estimated in three types of hypertensive rats: the spontaneously hypertensive rat (SHR), the DOCA-saline-treated rat and the renovascular rat (Goldblatt one-kidney, one-clip rat; 1K-1C). Alkaline phosphatase and sucrase specific activities have also been measured in purified jejunal brush-border membranes.
2. When compared with its normotensive age-matched control (WKY rat), the SHR has a lower activity of alkaline phosphatase in duodenal and jejunal crude membrane fractions, whereas a higher activity in colonic Na+, K+-ATPase is recorded. In purified jejunal brush-border membranes, lower alkaline phosphatase activity and higher sucrase activity were found. These differences occur in the young prehypertensive SHR as well as in the adult animal.
3. In the DOCA-treated rat, the only significant alteration in crude membrane fractions is a decreased Mg2+-ATPase activity at all regions of intestinal mucosa. In purified jejunal brush-border membranes both alkaline phosphatase and sucrase activities are increased at 4 or 7 weeks but especially at 13 weeks of hypertension.
4. In the 1K-1C rat, no significant modification appears in crude membrane fractions or in purified jejunal brush-border membranes, but a decrease in alkaline phosphatase and in sucrase activities is probable afer 13 weeks of hypertension.
5. Since alterations of the intestinal enzymes are different in the three types of hypertensive rats it is concluded that the changes are not secondary to the hypertension condition. In the SHR, these alterations are present in the young prehypertensive animal. Abnormalities of intestinal function may be implicated in the origin of genetic hypertension.
6. All recorded alterations represent 25-50% variations from control values. They indicate disturbances of intestinal ion transport in the three types of hypertensive animals.
The reproducibility of limb blood flow measurements in human volunteers at rest and after exercise by using mercury-in-Silastic strain gauge plethysmography under standardized conditions
Authors: Roberts D. H. , Tsao Y. , Breckenridge A. M. 
Published: August 2015

1. A study to assess the reproducibility of limb blood flow measurements by venous occlusion plethysmography using mercury-in-Silastic strain gauges was performed in six normal volunteers under standardized conditions.
2. Using this technique forearm and calf blood flow were measured at rest and between 2 and 3 min after submaximal exercise on six separate occasions over a 1 month period.
3. The mean coefficient of variation for resting forearm blood flow was 10.5% (range 7.8-15.6%).
4. The mean coefficient of variation for resting calf blood flow was 11.5% (range 7.4-14.2%).
5. The mean coefficient of variation for post-exercise calf blood flow was 13% (range 11.5-16.4%).
6. The results suggest that limb blood flow measurement by this technique may be useful in studies where serial measurements are required.
Effect of hypertension on the progress and prognosis of experimental focal glomerular sclerosis
Authors: Okuda Seiya , Tsuruda Hiroshi , Onoyama Kaoru , Oh Yukinori , Motomura Kenichi , Fujishima Masatoshi 
Published: August 2015

1. Effect of hypertension on progressive renal disease was examined in spontaneously hypertensive rats (SHR) with experimental focal glomerular sclerosis, produced by the intravenous administration of adriamycin (ADR). Serial changes of urinary protein, blood pressure and blood chemistry for 22 weeks after ADR-treatment, and renal histology at week 22, were compared between ADR-treated SHR (group ADR-HT) and ADR-treated SHR given antihypertensive drugs (group ADR-AH).
2. Hypertension persisted in group ADR-HT, while blood pressure markedly decreased in group ADR-AH, after oral administration of antihypertensive drugs (guanethidine and hydralazine).
3. Massive proteinuria, hypoalbuminaemia and hypercholesterolaemia were observed throughout the experiment both in group ADR-HT and in group ADR-AH. Urinary protein levels were significantly larger in the former at weeks 12 and 16.
4. Blood urea nitrogen and serum creatinine levels increased progressively from week 16 in the ADR-treated rats. The increase was more rapid in group ADR-HT than in group ADR-AH. In group ADR-HT, 10 of 25 rats died between weeks 20 and 22, whereas all in group ADR-AH survived.
5. Histologically, ADR-treated rats showed focal glomerular sclerosis with tubulointerstitial changes. The lesions were more extensive in group ADR-HT than in group ADR-AH.
6. We conclude that hypertension influences the progress and prognosis of chronic progressive renal disease, as induced by adriamycin.
The determination of oxalate in haemodialysate and plasma: A means to detect and study ‘hyperoxaluria’ in haemodialysed patients
Authors: Wolthers B. G. , Meijer S. , Tepper T. , Hayer M. , Elzinga H. 
Published: August 2015

1. In order to find out whether hyperoxaluria can be demonstrated in patients on chronic (twice a week) haemodialysis, a group of 13 patients was investigated. These included one patient with proven primary hyperoxaluria, one suspected of having this disease and 11 patients in whom no information was available as to their oxalate metabolism.
2. Oxalate concentrations in haemodialysate fractions and blood samples, taken before and after dialysis, were determined.
3. The patient with primary hyperoxaluria had a plasma oxalate concentration before dialysis above 100 μmol/l and after dialysis above 25 μmol/l, while the oxalate concentration in haemodialysate at the start of dialysis was above 25 μmol/l and at the end above 10 μmol/l. The patient suspected of hyperoxaluria had similar values. Of the remaining 11 patients, one was shown to exhibit a transient hyperoxaluria, but the others showed a normal oxalate metabolism.
4. A plasma oxalate/creatinine concentration ratio exceeding 0.1, and the calculated total quantity of oxalate removed by dialysis exceeding 2 mmol, also enabled a diagnosis of hyperoxaluria to be made.
5. Hyperoxaluria can still be demonstrated in patients, who because of renal failure are subjected to haemodialysis. Measurements of oxalate in haemodialysate and plasma are valuable in cases where kidney transplantations are considered, especially when the particular patient exhibits hyperoxaluria.
Superoxide dismutase isoenzymes in cerebrospinal fluid and plasma from patients with neuronal ceroid-lipofuscinoses
Authors: Marklund Stefan L. , Heiskala Hannu , Westermarck Tuomas , Santavuori Pirkko 
Published: August 2015

1. The neuronal ceroid-lipofuscinoses is a group of diseases characterized by a widespread accumulation in the body of pigments believed to be end-products of lipid-peroxidation damaged organelles. It was recently shown that cerebrospinal fluid from patients with infantile and juvenile neuronal ceroid-lipofuscinosis were less protective against superoxide radical-induced hydroxyl radical formation compared with controls [3].
2. The content of superoxide dismutase isoenzymes in cerebrospinal fluid and in plasma from patients with different forms of neuronal ceroid-lipofuscinosis was analysed. No significant difference from controls could be demonstrated in samples from patients with juvenile neuronal ceroid-lipofuscinosis. The few samples from patients with infantile and late infantile neuronal ceroid-lipofuscinosis analysed all fell within the range defined by the controls.
Changes in human plasma atrial natriuretic polypeptide concentration in normal subjects during passive leg raising and whole-body tilting
Authors: Ogihara Toshio , Shima Junko , Hara Hiroko , Kumahara Yuichi , Kangawa Kenji , Matsuo Hisayuki 
Published: August 2015

1. The effect of central venous pressure on release of human atrial natriuretic polypeptide (hANP) was studied by measuring the plasma hANP levels during passive leg raising to 60° and head up whole-body tilt at 60° in normal volunteers.
2. In ten subjects, after at least 1 h recumbency, both legs were raised passively 60° for 20 min. While the legs were raised the plasma hANP level increased significantly from a basal level of 101 ± 10 pg/ml (mean ± se) to a peak of 165 ± 15 pg/ml after 10 min, and returned to the basal level 10 min after the legs were lowered. The blood pressure and pulse rate were not affected by raising the legs.
3. The effect of head up whole-body tilt of 60° from the supine position, for 20 min, was examined in nine normal subjects. Their plasma hANP decreased transiently at 5 min in five of them and at 10 min or later in the remaining four subjects. Their blood pressure did not change but their pulse rate increased significantly while their body was being tilted.
4. These results suggest that secretion of hANP is regulated physiologically by changes in the central venous pressure.
Systemic and regional haemodynamic effects of a synthetic atrial natriuretic peptide in conscious rats
Authors: Caramelo Carlos , Fernandez-Cruz Arturo , Villamediana Luis M. , Sanz Elias , Rodriguez-Puyol Diego , Hernando Luis , López-Novoa Jose M. 
Published: August 2015

1. The effect of the intravenous injection of synthetic atrial natriuretic peptide (ANP, 2 μg) on systemic haemodynamics and blood flow to several organs has been studied in conscious rats by the radioactive microsphere technique.
2. ANP induced a 540% increase in sodium excretion and a 310% increase in urine flow. Mean arterial pressure decreased by 21 mmHg and the peripheral resistances decreased by 26%, without significant changes in cardiac output.
3. Renal blood flow increased by 37.7% and small intestine and portal blood flow increased by 39% and by 28% respectively. No other alterations in organ blood flows were observed.
4. From these data it can be concluded that atrial natriuretic peptide shows acute vascular relaxant properties, which seem to be specific for renal and mesenteric territories.
Enhanced rectal potassium secretion in chronic renal insufficiency: Evidence for large intestinal potassium adaptation in man
Authors: Sandle G. I. , Gaiger E. , Tapster S. , Goodshep T. H. J. 
Published: August 2015

1. The role of the large intestine in K+ excretion in chronic renal insufficiency was studied with a rectal dialysis technique in 14 normal subjects and eight normokalaemic, normotensive patients with chronic renal insufficiency.
2. At initial intraluminal K+ concentrations of 10, 20, 30 and 45 mmol/l, net K+ secretion in patients with renal insufficiency was significantly greater than in normal subjects by approximately 1.8 μmol h−1 cm−2. The increase in net K+ secretion was more marked in those patients with creatinine clearances of less than 10 ml/rnin. In contrast, there were no significant differences in net Na+ and water transport, transmucosal potential difference and plasma aldosterone concentrations between the two groups.
3. With an initial intraluminal K+ concentration of 30 mmol/l, the addition of amiloride (final concentration 1 mmol/l) to the rectal lumen decreased net Na+ absorption and transmucosal potential difference in normal subjects by 69% (P &lt; 0.005) and 31% (P &lt; 0.005) respectively, and in patients with renal insufficiency by 75% (P &lt; 0.05) and 36% (P &lt; 0.05) respectively, but there was no change in net K+ secretion in either group.
4. These results indicate that the K+ secretory capacity of the rectal mucosa increases in chronic renal insufficiency, and the large intestine may therefore contribute to the maintenance of K+ homoeostasis as renal K+ excretion declines. Increased rectal K+ secretion in renal insufficiency occurs independently of changes in plasma K+ and aldosterone concentrations, net Na+ absorption and transmucosal potential difference, and may reflect stimulation of an active K+ secretory process.
The effect of the dihydroxylated metabolites of vitamin D and dietary phosphate restriction on bone disease in uraemic rats
Authors: Main J. , Velasco N. , Heyes S. D. , Whiting P. , Fraser R. A. , Catto G. R. D. 
Published: August 2015

1. Uraemic rats maintained on either a high or a low phosphate diet for 12 weeks were allocated to one of the following oral vitamin D treatment groups and received: (a) 1,25-dihydroxycholecalciferol [1,25-(OH)2D3], (b) 24,25-dihydroxycholecalciferol [24,25-(OH)2D3], (c) both 1,25-(OH)2D3 and 24,25-(OH)2D3, or (d) no vitamin D supplements.
2. Mean serum creatinine concentrations were elevated to a similar extent in all groups. Mean serum concentrations of calcium, phosphate and alkaline phosphatase were not significantly different from normal in any of the groups.
3. In the group receiving the high phosphate diet and no vitamin D supplements, calcified bone area measured by quantitative computerized histomorphometry was significantly lower than in (i) the group receiving the low phosphate diet and no vitamin D supplements (0.01 &gt; P &gt; 0.001), and in (ii) the groups receiving high phosphate diet and either 1,25-(OH)2D3 (0.01 &gt; P &gt; 0.001) or 24,25-(OH)2D3 (0.01 &gt; P &gt; 0.001).
4. We conclude that (i) uraemic rats maintained on a high phosphate diet for 12 weeks develop skeletal demineralization, (ii) this process does not occur in rats on a low phosphate diet, and (iii) a decrease in calcified bone area may be prevented by treatment with either 1,25-(OH)2D3 or 24,25-(OH)2D3.
Withdrawal of salt supplementation from adrenalectomized Wistar rats distinguishes between those animals with, and those without, adrenocortical insufficiency
Authors: Gardiner S. M. , Bennett T. , MacDonald I. A. 
Published: August 2015

1. The effects of replacing a 1% NaCl drinking solution with Na+-free water for 2 days on body weight and fluid and electrolyte balances were studied in adrenalectomized and sham-operated rats.
2. Eight weeks after operation, after the animals had been drinking Na+-free water for 2 days, some adrenalectomized animals (about 75%; designated group 1) experienced body weight losses which were outside the 99% confidence limits for the sham-operated rats (– 9.2 to + 5.3 g) whereas the remainder (designated group 2) were indistinguishable from the controls.
3. The body weight loss in group 1 was associated with negative fluid, Na+ and K+ balances. In group 2 rats, fluid balance was maintained as well as in the sham-operated rats, but their handling of Na+ and K+ was different.
4. In a separate experiment, plasma aldosterone, corticosterone, catecholamine and solute concentrations were measured in adrenalectomized rats from groups 1 and 2 (selected on the basis of body weight loss whilst drinking Na+-free water) and sham-operated rats, after drinking Na+-free water for 2 days.
5. In group 1 animals, plasma aldosterone levels were unmeasurable and corticosterone was extremely low (less than 5% of controls). In group 2, aldosterone was measurable but low, and corticosterone was higher than in group 1 but lower than in sham-operated rats. In line with these findings, animals in group 1, but not those in group 2, were hyponatraemic and hyperkalemia These results are consistent with the activation of latent adrenocortical tissue in the group 2 animals.
6. We suggest that monitoring body weight changes resulting from drinking Na+-free water for 2 days provides a useful, non-invasive test for reliably distinguishing between those adrenalectomized animals with and those without adrenocortical insufficiency.
Effect of albumin on taurocholate uptake kinetics in rat liver
Authors: Aldini Rita , Roda Aldo , Morselli-Labate Antonio Maria , Simoni Patrizia , Roda Enrico , Barbara Luigi 
Published: August 2015

1. Isolated rat livers were perfused in a single pass with increasing doses of taurocholate with and without albumin in the perfusion media.
2. The kinetics of taurocholate uptake were thus evaluated.
3. In all the experiments, taurocholate uptake showed Michaelis-Menten kinetics. Increasing the albumin concentration in the medium resulted in an increase in the Km, without effect on the Vmax. When taurocholate and albumin were kept constant (20:1 molar ratio), the Vmax was significantly lower than in the other experiments.
4. These data suggest that taurocholate uptake shows saturation in the absence of albumin and that albumin reduces taurocholate uptake.