Search Results
Results 651 - 700 of 1266
< 9 10 11 12 13 14 15 16 17 18 19 >
Morild I - - 1987
Nine white leghorn chickens were injected i.m. with furosemide (10 to 60 mg/kg body weight) twice daily for 18 days. The birds were then anesthetized with a combination of equithesin and diazepam and the kidneys perfused via the heart. Kidney tissue was sectioned serially and the granular epithelioid cells were ...
de Mey C - - 1987
The haemodynamic effects of a standard meal were assessed in a balanced cross-over study in eight normal fasting subjects, investigated under conditions applicable to many drug tests. Both the supine and erect diastolic blood pressure were reduced on average by 10 mmHg over the 4 h following the meal. The ...
MacGregor G A - - 1987
There is controversy about the efficacy of sodium restriction in the treatment of hypertension. Short-term restriction of sodium intake in normotensive subjects causes little or no fall in blood pressure. This lack of response of blood pressure to sodium restriction appears to be due, at least in part, to a ...
Stanek B - - 1987
In hepatic cirrhosis neurohumoral vasoconstrictor systems are activated to compensate for circulatory disturbances. To study the renin-angiotensin-aldosterone system in more detail, angiotensin converting enzyme in 15 patients with advanced liver disease was inhibited with captopril after moderate sodium restriction. Captopril caused an increase in plasma renin activity (p less than ...
Nordlander M - - 1987
The baroreflex control of heart rate will be rapidly reset to operate at a lower pressure level after blood pressure reduction by felodipine. The present study investigates whether the baroreflex control of renin release in spontaneously hypertensive rats (SHR) will also be reset after prolonged felodipine administration. Conscious SHR, fitted ...
Takabatake T - - 1987
The immediate haemodynamic effects of the calcium antagonist nilvadipine have been studied in ten patients with established mild essential hypertension. Nilvadipine 4 mg p.o. reduced both the systolic and diastolic blood pressures within 60 min, associated with a fall in total peripheral resistance and an increase in heart rate and ...
Wood J M - - 1987
The primate-specific renin inhibitor CGP 29287 (30 mg/kg/d, n = 5) or the converting-enzyme inhibitor CGS 14831 (30 mg/kg/d, n = 8) were administered by continuous intraperitoneal infusion via osmotic minipumps to normotensive marmosets fed a low salt diet. CGP 29287 and CGS 14831 induced a similar reduction in blood ...
Omata K - - 1986
To determine the role of endogenous prostaglandins and sodium balance in the maintenance of high blood pressure in chronic two-kidney, one clip hypertension in rats, we studied the effect of indomethacin infusion on the reversal of hypertension by unclipping. Indomethacin was infused after control measurements, and blood pressure was monitored ...
Smith S A - - 1986
The influence of acute and chronic treatment with felodipine on ambulatory intra-arterial blood pressure, certain cardiac reflexes, and plasma renin activity was studied in nine patients with essential hypertension. Acute oral administration of the drug caused a significant reduction in blood pressure associated with an increase in heart rate mediated ...
Franklin S S - - 1986
This study examined the relationship between arterial blood pressure and plasma norepinephrine levels during 12 hours of monitored sleep in a 35-year-old man in whom neurogenic hypertension developed immediately after surgical removal of a large hemangioblastoma at the obex region of the cervical-medullary junction. Plasma norepinephrine levels throughout the 12-hour ...
Olivari M T - - 1986
The reduced responsiveness of the renin-angiotensin system to hemodynamic changes in patients with congestive heart failure (CHF) could be due to a defect of the juxtaglomerular apparatus. To test this hypothesis, the responses to viprostol, an analog of prostaglandin E2 (PGE2) that is known to stimulate both the macula densa ...
Nicod P - - 1986
The pathophysiological role of an increase in circulating vasopressin in sustaining global and regional vasoconstriction in patients with congestive heart failure has not been established, particularly in patients with hyponatraemia. To assess this further, 20 patients with congestive heart failure refractory to digoxin and diuretics were studied before and 60 ...
Brunner H R - - 1986
The renin-angiotensin system is known to respond to various stimuli with a marked increase in its activity. This phenomenon is well known in relationship to changes in sodium balance. Thus, the antihypertensive effect of diuretics is often blunted or even abolished by an excessive renin response. Water deprivation and alpha-adrenoceptor ...
Swales J D - - 1986
There is evidence that neither activation of the renin-angiotensin system nor changes in sodium balance can fully explain the maintenance of blood pressure in Goldblatt hypertension. Thus, in Goldblatt two-kidney, one clip hypertension in the rat sodium balance is negative and in hypertension of a few months' duration plasma renin ...
Haas E - - 1986
Some of Dr. Goldblatt's important contributions during a notable research career of more than 50 years are reviewed. The research on rickets (1922-1932), culminating in the discovery of the antirachitic effect of sterol irradiated with ultraviolet light. The research on cancer (1930-1974), demonstrating the malignant transformation of normal fibroblasts caused ...
Smits P - - 1986
The circulatory response to coffee was studied in 10 normotensive, 10 bilaterally adrenalectomized, and 10 hypertensive subjects. In the normotensive group, drinking coffee exerted a rise in blood pressure (+5.1/+11.5 mm Hg), a fall in heart rate (-6.0 bpm), a rise in plasma epinephrine (+257.2%), and no change in plasma ...
Sved A F - - 1986
The roles of vasopressin, the sympathoadrenal system, and the renin-angiotensin system in the production of hypertension after bilateral destruction of the nucleus tractus solitarius (NTS) were examined in chloralose-anesthetized rats. Since the activity of the renin-angiotensin system is high in anesthetized rats, additional studies were performed in unanesthetized, freely moving ...
Arnolda L - - 1986
Vasopressin's role as a vasoconstrictor in chronic heart failure, was examined in rabbits with adriamycin cardiomyopathic congestive heart failure. Chronic adriamycin treatment resulted in a decrease in cardiac output (829 +/- 38-610 +/- 36 ml/min, P less than 0.005) and blood pressure (83 +/- 2-76 +/- 3 mmHg, P less ...
Pegram B L - - 1986
The atrial natriuretic hormone (ANH) alters cardiovascular function independent of changes in body fluid volume. Most investigators agree that ANH decreases mean arterial pressure (MAP). However, although some investigators have observed a decrease in total peripheral resistance in association with the decrease in MAP, a more frequent observation has been ...
Eggena P - - 1986
The individual components of the renin-angiotensin system has been identified in numerous tissues. In this study we have examined whether a functional renin-angiotensin system is operative in several hog tissues including brain, aorta, and liver. The contribution of tissue renin substrate to the rate of local angiotensin generation was also ...
Levine T B - - 1986
The ability of neurohumoral reflex control mechanisms to respond to a vasodilator mediated alteration in hemodynamic status was studied. A sodium nitroprusside infusion was administered to 5 normal subjects and 47 patients with severe congestive heart failure resulting in significant decreases in mean arterial pressure and in systemic vascular resistance. ...
Kravik S E - - 1986
Blood pressure, pulse rate (PR), serum osmolality and electrolytes, as well as plasma vasopressin (PVP) and plasma renin activity (PRA), were measured in five men and two women [mean age 38.6 +/- 3.9 (SE) yr] before, during, and after inflation of an antigravity suit that covered the legs and abdomen. ...
Okamura T - - 1986
The possible role of the renin-angiotensin system in the maintenance of hypertension in two-kidney, one clip hypertensive rats was studied. Plasma renin activity rose rapidly and markedly in association with the elevation of blood pressure and then decreased gradually, although blood pressure remained high. Renin activity in the lung, aorta, ...
Looareesuwan S - - 1986
Chloroquine diphosphate (3 mg base kg-1) was given by constant rate intravenous injection over 10 min to 12 healthy adult male volunteers. Plasma concentrations of chloroquine and the principal metabolite desethylchloroquine, electrocardiograph intervals, and arterial blood pressure were measured at frequent intervals to determine the relationship between cardiovascular effects and ...
Dickstein K - - 1986
The acute hemodynamic and hormonal effects of the oral angiotensin-converting enzyme (ACE) inhibitor lisinopril (MK-521) were assessed over a period of 96 hours in 12 patients with heart failure. This compound is the lysine analogue of enalaprilat (MK-422), is biologically active following absorption, and is cleared via the urine without ...
Wood C E - - 1986
This study was designed to investigate adrenocorticotropin (ACTH), cortisol, and renin responses to nitroprusside-induced hypotension in adult sheep. Five sheep were surgically prepared with carotid arterial skin loops at least 1 yr before these experiments. After catheterization of the carotid arteries and external jugular veins the sheep were infused with ...
Atkinson J - - 1986
This study investigated whether the specific alpha-antagonist, prazosin, stimulated basal plasma renin levels and heart rate. Furthermore the beta-adrenergic nervous system was also investigated to ascertain whether it was involved in this effect. Prazosin (0.1 or 1 mg/kg) was injected subcutaneously (s.c.) to conscious normotensive rats, either alone or in ...
Fitzpatrick M A - - 1986
Abnormalities of renin release and of venous distensibility have been described in essential hypertension. We have postulated that decreased venous distensibility could contribute to the blunted renin response to upright posture in hypertension. Stiffer veins might prevent venous pooling in the lower extremities, which in turn might affect the stretch ...
Resnick L M - - 1986
Alterations of calcium metabolism in hypertensive disease have been increasingly observed, although the specific manner in which these alterations contribute to the increased blood pressure remains unclear. We have studied calcium metabolism in essential hypertension and have adopted an approach based on analysis of renin system activity, which emphasizes the ...
Blackburn H - - 1986
Cross-sectional comparisons of athletes and nonathletes and of active and inactive occupations do not support the hypothesis that habitual physical activity protects against hypertension. However, more powerful cohort studies tend to support the hypothesis but indicate that the effect, if any, is not great. Conditioning level experimental exercise studies suggest, ...
Bailey R W - - 1986
The nonocclusive component of ischemic colitis in anesthetized pigs was mimicked using cardiogenic shock produced by pericardial tamponade. Increases in pericardial pressure produced decreases in arterial pressure (PA) and cardiac output (CO), with corresponding rises in total peripheral resistance (i.e., cardiogenic shock). This was associated with marked reductions in blood ...
Gavras I - - 1986
We studied the effect of various adrenergic components on vasopressin in groups of anephric rats. Pharmacological interventions included alpha 1-, alpha 2-, and beta-adrenergic receptor blockade and infusions of sodium nitroprusside to achieve a baseline blood pressure fall similar to that obtained by alpha 1-blockade, followed by hypertonic saline infusion ...
Clementi G - - 1986
Salmon calcitonin, centrally injected, increased plasma renin activity and blood pressure in rats. It is possible that the peptide through an action on the central serotonergic tone stimulated plasma renin activity with subsequent enhancement of blood pressure. Conversely, peripheral administration of the peptide increased plasma renin activity but did not ...
Gossain V V - - 1986
It is generally recognized that smoking is associated with an increased risk for the development of coronary artery disease. Since it has been suggested that increased plasma renin activity (PRA) may be a risk factor for cardiovascular disease, PRA was measured in a group of smokers and nonsmokers. PRA was ...
Obika L F - - 1986
The effect of bilateral nephrectomy, and administration of an inhibitor of angiotensin converting enzyme, on the recovery of arterial blood pressure after hemorrhage (loss of 1% of b.wt), was studied in male Sprague-Dawley rats. Neither manoeuver significantly affected the recovery of blood pressure within the first 10 min after hemorrhage. ...
Muller F B - - 1986
To develop a screening test for identifying renovascular hypertension, the blood pressure and plasma renin activity responses to an oral test dose of captopril were studied in 246 quietly seated hypertensive patients. The following criteria were developed that exploit the hyperresponsiveness of renin secretion in renovascular hypertensive patients: a 60-minute ...
Rydstedt L L - - 1986
To assess the contribution of the renin-angiotensin-aldosterone system and renal hemodynamics to acute renal sodium handling in essential hypertension we studied 21 subjects who had essential hypertension (16 with normal renin, 5 with low renin) and 9 normal subjects. All were in balance on a 10 mEq sodium intake before ...
McKenna F - - 1986
The role of the renin-aldosterone system in predicting the hypotensive effect of beta-blockade is controversial. We have measured blood pressure, heart rate, plasma active renin, prorenin and aldosterone in 44 hypertensive patients before and after 18 weeks treatment with either nadolol or metoprolol in a double blind randomized study. Prorenin ...
Uchiyama M - - 1986
37 children aged 7-14 years with a history of repetitive fainting (vasovagal syncope) were studied. Plasma renin activity (PRA), blood pressure and heart rate were measured before and after standing for 15 min. Standing PRA was significantly higher in cases of fainting (n = 14) than in cases of nonfainting ...
Ocon Pujadas J - - 1986
We studied 37 patients with various degrees of hypertension and a small unilateral kidney. Renal vein renin studies were shown to be positive on 19 occasions and negative on 18. Of those positive, 10 had severe and 1 moderate hypertension. Surgery cured 63.3%. In 27% blood pressure improved and 1 ...
Urmancheva T G - - 1986
The influence of experimental neurosis due to repeated conflict situations on blood pressure was studied in male monkeys. All animals developed hypertension demonstrable in the conscious state but which disappeared under pentobarbital anaesthesia. Both in conscious and anaesthetized animals, the pulse pressure was in-elevated. The hypertension was accompanied by increased ...
Kawano S - - 1986
A case of hypertension secondary to unilateral hydronephrosis due to congenital obstruction of ureteropelvic junction in a 6-year-old boy is reported. Preoperatively, the plasma renin activity (PRA) in the peripheral vein and in the affected kidney was elevated. Blood pressure decreased significantly following administration of converting enzyme inhibitor. After nephrectomy, ...
Rossi N F - - 1986
Arginine vasopressin (AVP) not only influences renal water metabolism but also has profound cardiovascular effects. Physiologic levels of the hormone produce a pressor response in the basal state when vasoregulatory reflex mechanisms are interrupted. During hypovolemia, vasopressin affects systemic blood pressure independent of the renin-angiotensin system and efferent sympathetic pathways. ...
Szilagyi J E - - 1986
It has now been established that there is an interaction between the cardiovascular control systems and opiate substances. To assess the role of endogenous opiates in the long-term control of blood pressure, the opiate antagonist naloxone (0.5 mg/kg/24 h) was infused intravenously for 7 days. Chronic blockade of endogenous opiates ...
de Leeuw P W - - 1986
To assess dose-related effects of enalapril, we treated eight hospitalized hypertensive patients receiving constant sodium intake with incremental doses of this new angiotensin converting-enzyme blocking drug. After a few days of placebo treatment, enalapril was given in single daily doses, starting with 1.25 mg and increasing dosage until blood pressure ...
Virdis R - - 1986
Adult Turner syndrome (TS) patients frequently present hypertension. To clarify the pathogenesis of this hypertension we examined the blood pressure (BP) behaviour and the renin-angiotensin-aldosterone system in 31 TS patients (2-22 years of age). BP levels were occasionally elevated in 47% of the subjects and constantly elevated in 23%. Most ...
Kiowski W - - 1985
Age, race, pretreatment blood pressure and plasma renin activity have been related to the antihypertensive response to calcium antagonists in studies that included 215 patients with mild to moderate essential hypertension. Adverse effects necessitated withdrawal from therapy in about 10% of the patients. All calcium antagonists lowered blood pressure significantly ...
Resnick L M - - 1985
The renin-angiotensin-aldosterone system regulates blood pressure and volume homeostasis in addition to sodium and potassium metabolism, and may be linked to divalent cation metabolism as well as hypertensive disease. In essential hypertension, circulating serum magnesium and Ca++, and the calcium regulating hormones, parathyroid hormone, calcitonin and 1,25 dihydroxyvitamin (1,25D) are ...
Hollenberg N K - - 1985
Whether or not the kidney is involved in the genesis of hypertension in an individual patient, it becomes a major determinant of the response to antihypertensive therapy once a treatment strategy is adopted. The major mechanisms through which the kidney influences blood pressure are renin release and sodium retention, either ...
Johnston C I - - 1985
Recently, there has been an explosion of knowledge on vasopressin, including its neuro-anatomy, biochemistry and physiology. Recent work demonstrates extensive extra-hypothalamic vasopressinergic projections from the SON and PVN. Of particular importance are projections to the cardiovascular medullary centres. Conversely, the SON and PVN receive reciprocal catecholaminergic innervation from autonomic medullary ...
< 9 10 11 12 13 14 15 16 17 18 19 >