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Ganong W F - - 1984
Neuropeptides can affect cardiovascular function in various ways. They can serve as cotransmitters in the autonomic nervous system; for example, vasoactive intestinal peptide (VIP) is released with acetylcholine and neuropeptide Y with norepinephrine from postganglionic neurons. Substance P and, presumably, other peptides can can affect cardiovascular function when released near ...
Grassi G - - 1984
Animal studies have shown that renin release is reflexly modulated by cardiopulmonary and arterial baroreceptors, and that during changes in posture the former receptors play a major role. This role has been challenged in man, however, by reflex modulation of renin secretion which has been claimed to take place only ...
Niarchos A P - - 1984
Of 103 patients with isolated systolic hypertension, 71 were treated with diuretics and another 32 with low-sodium diet. In the 71 who were treated with diuretics, body weight decreased from 69.48 +/- 1.47 to 68.60 +/- 1.45 kg (p less than 0.0005) and systolic blood pressure from 178 +/- to ...
Lee M E - - 1984
The relative roles of cardiopulmonary, sinoaortic, and renal baroreceptors in the regulation of plasma renin activity (PRA) were evaluated in dogs with chronically implanted cuffs around the ascending aorta proximal to the brachiocephalic artery, the abdominal aorta just proximal to both renal arteries, or both. Inflation of either cuff was ...
Re R N - - 1984
The renin-angiotensin system is a major determinant of arterial pressure and intravascular volume in human beings. Recent evidence, however, suggests that renin can be synthesized at local tissue sites and that these local renin-angiotensin systems subserve important physiologic functions. In addition, it appears that there exist intracellular renin-angiotensin "systems" capable ...
Oliver J A - - 1984
Renin is present in vascular smooth muscle cells and has been shown to coexist with angiotensins I (AI) and II (AII) in many cell types. Accordingly, we postulated that the renin-angiotensin system controls vascular tone, not by the action of circulating renal renin but rather, by the local generation of ...
Cohn J N - - 1984
Hemodynamics, plasma norepinephrine, and plasma renin activity were measured at supine rest in 106 patients (83 men and 23 women) with moderate to severe congestive heart failure. During follow-up lasting 1 to 62 months, 60 patients died (57 per cent); 47 per cent of the deaths were sudden, and 45 ...
Greminger P - - 1984
To analyse the role of the renin angiotensin system in the pathogenesis of hypertension in Cushing's syndrome ten patients with hypercorticism (five with pituitary hypothalamic dysfunction, three with adrenal adenomas and two with adrenal carcinomas) received a single oral dose of 25 mg captopril. Mean arterial pressure was then determined ...
Simon G - - 1984
The effect of long-term treatment with nitrendipine on systemic pressor responses to norepinephrine (NE) and angiotensin II (AII) was evaluated in 11 subjects with mild, uncomplicated hypertension. Pressor responses to NE and AII were measured at the end of a 4-wk placebo period and after 5 wk treatment with nitrendipine ...
Niarchos A P - - 1984
The role of the renin system in the maintenance of the elevated systolic blood pressure in isolated systolic hypertension was investigated in 31 patients who received long-term treatment with propranolol (120 mg daily) and in another group of 22 patients with isolated systolic hypertension who received a test dose of ...
Olivari M T - - 1984
Acute hemodynamic and hormonal responses to a single dose of indoramin, an alpha 1-antagonist, were evaluated in 11 subjects with severe chronic congestive heart failure. A hemodynamic effect began within 1 hr of indoramin and persisted during the 6 hr of hemodynamic monitoring. Decreased right and left ventricular filling pressures ...
Müller F B - - 1984
A wide variety of drug treatments are available for the management of hypertension. Often, effective therapy is found only through a process of elimination. A more pathophysiologically oriented method of choosing therapy is based on classification of patients into those with low-, normal-, and high-renin hypertension. In the past, for ...
Daugirdas J T - - 1984
Hemodynamic response to volume depletion by isolated ultrafiltration was compared in uremic (U) and nonuremic (N) conscious dogs. Fluid was removed at a constant rate until mean arterial pressure (MAP) decreased to less than 80 mmHg. Initial MAP was higher in the uremic dogs [132 +/- 8.6 (SD) mmHg] than ...
Cody R J - - 1984
The renin-angiotensin system is an important regulator of vascular resistance in many patients with hypertension and congestive heart failure. To quantitatively evaluate this contribution requires correlation of markers of the renin-angiotensin system with haemodynamic parameters, notably blood pressure, cardiac output, and calculated systemic vascular resistance. In addition, to determine ventricular ...
Osterziel K J - - 1984
In a previous paper we reported that in pigs and dogs hindlimb compression causes large blood pressure increases which appear to be neurogenic. The present studies explore the utility of this non-invasive pressor model by determining the duration of the blood pressure increase, and by providing definitive evidence that the ...
Lasson A - - 1984
Changes in the kallikrein-kinin system were analysed in 19 attacks of acute pancreatitis in man and correlated to the severity and clinical course of the disease. Prekallikrein, kininogen and kallikrein inhibition were significantly lower in blood in severe attacks than in moderate or mild attacks. These changes were even more ...
Lindop G B - - 1984
An antibody to pure human renin and an immunoperoxidase technique were used to stain immunoreactive renin in nephroblastomas. In an unselected series of surgically removed nephroblastomas immunoreactive renin was found in 10 of 19 tumours (53%). Tissue obtained at necropsy from 12 cases of disseminated nephroblastoma was also studied, and ...
Fouad F M - - 1984
The antihypertensive effects of nitrendipine were evaluated in 12 subjects with hypertension, one of whom could not tolerate the drug for more than 3 days; hence hemodynamics were studied in the 11 subjects who were treated for 2 wk. In one patient taking 40 mg twice a day, blood pressure ...
Brooks D P - - 1984
Infusion of oxytocin into one vertebral artery of anesthetized dogs did not alter plasma vasopressin concentration, blood pressure or heart rate. However, there was a significant (p less than 0.01) increase in plasma renin activity (PRA; delta = 7.6 +/- 2.3 ng/ml X h). A 35% hemorrhage caused blood pressure ...
Kopp U C - - 1984
The interaction between the neural and nonneural mechanisms in the control of renin secretion rate was studied in anesthetized vagotomized dogs at renal arterial pressures of 170, 130, 90, and 50 mmHg. Left renal nerves were stimulated (RNS) at either 0.075, 0.3, or 0.7 Hz and the right kidney was ...
Conway J - - 1984
In order to study blood pressure variability we have measured blood pressure, heart rate, plasma noradrenaline and adrenaline concentration and plasma renin activity during sleep and during the waking process in 20 subjects with borderline hypertension. The responses to a number of standardized tests were also measured. These were reading, ...
Zabludowski J R - - 1984
Ketanserin, a 5-HT type 2 receptor antagonist, was administered intravenously to nine patients with essential hypertension in a double-blind placebo controlled study to investigate the drug's effects on blood pressure, heart rate, the renin-angiotensin system and sympatho-adrenal function. Average blood-pressure for the group prior to injection of the drug was ...
Townsend G E - - 1984
The role of the renin-angiotensin system in the aetiology of perioperative hypertension was studied in 15 previously normotensive patients undergoing coronary artery surgery and anaesthetized with fentanyl. Measurements of plasma renin activity were made at intervals before and during cardiopulmonary bypass (CPB). In addition, angiotensin II blockade with saralasin was ...
Niarchos A P - - 1984
In 30 patients with isolated systolic systemic hypertension, diuretic therapy decreased body weight from 71.33 +/- 2.67 to 70.37 +/- 2.65 kg (p less than 0.0005) and the systolic blood pressure from 174 +/- 3 to 156 +/- 3 mm Hg (p less than 0.0005). Diastolic blood pressure and heart ...
Valvo E - - 1984
Timolol, a non-cardioselective beta-blocking agent, was administered orally after 2 weeks of placebo to 14 patients with essential hypertension for 8 weeks following 1-4 weeks of dose-ranging period. Patients were first hospitalized and submitted to a diagnostic workup. They were placed on a diet containing 100 mEq of Na+ and ...
Michel J B - - 1984
The effects on blood pressure of an antiserum against pure human kidney renin were studied in conscious and anesthetized (pentobarbital, 24 mg X kg-1 i.p.) small new world monkeys (common marmosets). The antiserum inhibited the enzymatic activity of renin by 50% in a dilution of 1:45,000 in marmoset and 1:50,000 ...
Dzau V J - - 1984
The use of antirenin antibody and its fragments as specific tools for the analysis of the role of renin in blood pressure regulation is assessed in this study. Specific immunoglobulin G (IgG) or its antibody fragments (Fab) raised against purified canine renal renin were employed. These agents had no effect ...
Hodsman G P - - 1984
The immediate and long-term effects of enalapril (MK421) and its lysine analogue (MK521) in once-daily dosage, were compared in a study of 12 normal subjects. Both compounds lowered blood pressure equally throughout 24 h without causing tachycardia. The biochemical changes with MK521 were more sustained than with MK421, but this ...
Sundet W D - - 1984
The effects of vanadate on cardiovascular function and on the secretion of renin and vasopressin were investigated by infusing sodium orthovanadate (0.32 mu mole/kg X min) intravenously into five conscious dogs. Vanadate caused significant increases in mean arterial pressure, total peripheral resistance, pulmonary arterial pressure, and cardiac output. These data ...
Bacher S - - 1984
The magnitude and the persistence of blood pressure reduction by dihydralazine and urapidil were investigated following treatment over a period of 4 days. The experiments were performed on six normotensive dogs, trained to submit to puncture of the femoral artery and to stand quietly in a special frame. The first-dose ...
Riegger G A - - 1984
Hormonal factors may be important in the regulation of peripheral vascular resistance (PVR) in congestive heart failure (CHF). The role of the renin-angiotensin system in the development of CHF was studied in 16 unanesthetized dogs. CHF was induced by rapid right ventricular pacing, with and without chronic converting-enzyme inhibition (CEI) ...
Waeber B - - 1984
Such compounds as clonidine, guanabenz and guanfacine, which stimulate central alpha-adrenoceptors, reduce blood pressure predominantly by reducing sympathetic outflow. Notwithstanding, they also tend to reduce renin secretion, aldosterone, and even vasopressin levels. In some clinical settings, inactivation of the renin-angiotensin system may contribute to their antihypertensive effect. In addition, the ...
Buckley J P - - 1984
Initial studies were undertaken to investigate the effects of prolonged administration of angiotensin II (AII), 1 micrograms twice daily, via the lateral ventricles to mongrel dogs on arterial blood pressure and to determine if sodium intake was essential for the development of hypertension. Increasing AII levels in the cerebrospinal fluid ...
Ocón J - - 1984
We applied the central renal vein renin ratios in a group of patients with unilateral renal tuberculosis and hypertension to see whether the diseased kidney was involved in the pathogenesis of the elevated blood pressure. Of 20 patients 11 were nephrectomized, 7 had positive renal vein renin ratios and normal ...
Shepherd A M - - 1984
We previously have demonstrated that the sympathetic nervous system is activated proportionately to the degree of vasodepression induced in hypertensive patients. In the present study, the role of the renin-angiotensin system in modulating the vasodepressor response to sodium nitroprusside was examined. Nine hospitalized hypertensive patients receiving a diuretic were given ...
Velasco M - - 1984
The effect of guanfacine and hydrallazine on cardiovascular haemodynamics and on sympathetic nervous activity has been studied in 16 patients with essential hypertension. Two groups of patients were investigated: in Group A guanfacine brought the blood pressure back to normal (diastolic blood pressure less than or equal to 90 mmHg), ...
Buggy J - - 1984
Periventricular forebrain regions participate in body fluid and cardiovascular regulatory mechanisms that are intimately related to neural participation in experimental hypertension. Ablation of preoptic-hypothalamic periventricular tissue surrounding the anteroventral third ventricle (AV3V) disrupts both angiotensin (AngII) and sodium regulatory mechanisms and prevents experimental hypertension in either renin-dependent or -independent models. ...
Sybertz E J - - 1984
The synthetic tetradecapeptide renin substrate (TDP; Asp-arg-val-tyr-ile-his-pro-phe-his-leu-leu-val-tyr-ser) has been employed frequently to elucidate the enzymatic action of renin in vitro and, to a lesser extent, in vivo. We assessed the utility of TDP as a renin substrate in vivo using conscious spontaneously hypertensive rats. Intravenous injection of TDP (1 and ...
Slater E E - - 1984
Polyclonal antisera raised against pure human renin normalize renin-dependent blood pressure elevation in the monkey (M. fascicularis). In vitro, comparable inhibition of either human or monkey plasma renin by the antisera was demonstrated. In vivo, intravenous infusion of 2 ml of antisera did not change mean arterial pressure of salt-repleted ...
Del Gaudio A - - 1984
A rare case of extra-adrenal pheochromocytoma occurring in the aorto-caval space and responsible for right artery stenosis, is described. The pheochromocytoma was excised and the blood flow in the renal artery restored. The heightened blood pressure, of dual origin, returned to normal after the operation. Three years after surgery the ...
Dzau V J - - 1983
Animal models of experimental heart failure have provided the basis of our current understanding of the role of the kidney and neurohumoral mechanisms in clinical congestive heart failure (CHF). The vasoconstrictor hormones, i.e., the renin-angiotensin system (RAS) and the sympathoadrenal and vasopressin systems, are activated in acute cardiac decompensation and ...
Derkx F H - - 1983
The pressor effect of arginine vasopressin (AVP) is thought to be mediated by a calcium-dependent mechanism (V1-receptor) whereas its antidiuretic effect depends on c-AMP (V2-receptor). 1-Desamino-8-D-arginine-vasopressin (DDAVP) is possibly an antagonist on the V1-receptor and may therefore be used for assessing the role of endogenous AVP in blood pressure regulation. ...
Vlachakis N D - - 1983
We measured the first dosage effect and the long-term effect of lofexidine on blood pressure, heart rate, plasma catecholamines, and their major metabolites in 16 patients with primary hypertension who were receiving 50 mg hydrochlorothiazide twice a day while they were recumbent and upright and during isometric handgrip contraction. We ...
Smith R S - - 1983
We have studied several factors that may cause hypertension in renal transplant recipients. Cardiac output measurements suggest that hypertension is maintained by an increase in total peripheral resistance. Plasma noradrenaline concentration was significantly higher in both normotensive and hypertensive patients than in matched normal subjects. Plasma noradrenaline rose significantly in ...
de Leeuw P W - - 1983
In this study we investigated the role of the renin-angiotensin system and the adrenergic system in the hypertensive response during and following coronary bypass surgery. Arterial blood samples for measurement of active renin, angiotensin II, aldosterone and catecholamines were drawn before, during and in the first period after coronary artery ...
Mikami H - - 1983
We have investigated the relative importance of angiotensin and vasopressin in the regulation of arterial pressure following permanent interruption of supraspinal sympathetic influences. To accomplish this aim, the spinal cord of 12 dogs was transected just above the intervertebral foramen of C-6; several days later, we gave first a potent ...
Staessen J - - 1983
The contribution of beta 1-adrenoceptors to the regulation of plasma renin activity was investigated in nine healthy sodium-replete volunteers: seven subjects received a cumulative intravenous dose of 75 micrograms/kg prenalterol, a predominant beta 1-adrenoceptor agonist, and two subjects only vehiculum. In the seven actively treated subjects beta 1-adrenoceptor agonism increased ...
Seto S - - 1983
We studied the effect of aprotinin, a reversible inhibitor of kallikrein and other serine proteases, upon urinary kallikrein and kinin excretion, renal function and hemodynamics, blood pressure, and plasma renin activity (PRA). When aprotinin was administered to anesthetized rats at 10,000 KIU/kg as a bolus, and at 1000 KIU/kg/min infusion ...
Russell G I - - 1983
The hemodynamic changes associated with reversal of Goldblatt two-kidney, one-clip hypertension in conscious rats were studied using radioactive microspheres. In both the early phase (less than 6 wk from clipping) when plasma renin was elevated and the chronic phase (greater than 4 mo) when plasma renin was normal, hypertension was ...
de Leeuw P W - - 1983
To assess the effects of enalapril eight hospitalized hypertensive patients on constant sodium intake were treated with incremental doses of this angiotensin converting enzyme blocking drug. After four days of placebo treatment enalapril was given in single daily doses, starting with 1.25 mg and increasing until blood pressure was adequately ...
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