Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Human alpha atrial natriuretic peptide (ANP) was infused intravenously for 1 h in eight healthy salt-replete men on two occasions, with and without pretreatment with (+)-sulpiride. 2. ANP increased sodium excretion and urine flow rate but did not alter blood pressure or plasma renin activity. 3. (+)-sulpiride had no significant effect on baseline creatinine clearance, sodium excretion or urine flow rate and did not alter the increases in these parameters with ANP. 4. It is unlikely that the renal effects of ANP are mediated by dopamine DA1-receptors in man.
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PMID:The renal effects of atrial natriuretic peptide in man are not attenuated by (+)-sulpiride. 252 27

The effect of a single oral dose of 100 mg of fenoldopam on renal function and blood pressure was investigated in seven healthy male subjects in a double-blind placebo controlled study. Mean diastolic blood pressure fell by 10 mm Hg, 45 min after oral dosing and then gradually returned to baseline values. There was an increase in pulse rate and a delayed rise in systolic blood pressure. Measured from 30 to 120 min after drug ingestion, mean effective renal plasma flow increased to 158% of the value observed after placebo; mean glomerular filtration rate rose to 109% of the placebo value. Measured from 120 to 210 min after administration of the drug, effective renal plasma flow and glomerular filtration rate had returned to baseline values. Fenoldopam produced a small increase in the mean sodium excretion rate which was not significantly different from the fall after placebo. No change was detected in urine flow or potassium excretion rate. Mean plasma renin activity increased three-fold 1 h after oral dosing. Plasma aldosterone did not show a parallel increase although the plasma concentration at 1 h was significantly higher than after placebo. The results show a pronounced renal vasodilator effect lasting about 2 h. The findings are consistent with marked DA1 receptor agonist activity.
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PMID:The effect of oral fenoldopam (SKF 82526-J), a peripheral dopamine receptor agonist, on blood pressure and renal function in normal man. 285 15

A series of studies were undertaken to assess the effect of oral fenoldopam, a specific DA1 dopamine receptor agonist on blood pressure and renal function in patients with mild essential hypertension. Six patients with essential hypertension were entered into a dose-ranging study and received either placebo, 25, 50 or 100 mg fenoldopam. A significant, dose-related reduction in diastolic blood pressure, and increase in heart rate was demonstrated (both P less than 0.05), maximal at 45 min to 1 h. Fenoldopam increased plasma renin activity. In a double-blind study, seven patients received a single dose of fenoldopam 100 mg or placebo. Fenoldopam produced a significant fall in systolic (P less than 0.05) and diastolic (P less than 0.01) blood pressure and renal vascular resistance (P less than 0.01). Urine flow rate (P less than 0.05), sodium excretion (P less than 0.01), plasma renin activity (P less than 0.05) and plasma aldosterone (P less than 0.05) increased. Five patients underwent measurement of the above parameters following a single dose of fenoldopam 100 mg with a repeat of these measurements after they had taken fenoldopam 100 mg four times daily for 1 month. The acute response of blood pressure to the single dose appeared unchanged but tachyphylaxis was evident in the responses of heart rate, plasma renin activity and plasma aldosterone.
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PMID:Studies with fenoldopam, a dopamine receptor DA1 agonist, in essential hypertension. 286 48

Dopamine affects renal hemodynamics, renal tubular functions, and the secretion of renin. We have studied the renal effects of SK&F 82526 (an agonist which is selective for the DA1 subclass of dopamine receptors) in anesthetized rats. Infused intravenously at 0.005 mumol/min/kg, this drug increased renal plasma flow and the clearances of PAH and insulin, effects which are consistent with decreased renovascular resistance. Concomitantly, urine flow and K excretion increased, and Na excretion tended to increase. All these effects of SK&F 82526 were antagonized by intravenous metoclopramide (1 mumol/min/kg). Despite its diuretic effect and despite its lack of effect on arterial blood pressure, SK&F 82526 increased arterial plasma renin concentration, suggesting a stimulatory effect on renin secretory rate. Taken together, our results demonstrate that the renal effects of SK&F 82526 mimic those of dopamine.
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PMID:Renal effects of SK&F 82526 in anesthetized rats. 287 68

The effect of fenoldopam, a selective DA1-agonist, on the plasma aldosterone response to metoclopramide was studied in six hypertensive patients included in a multicentre double-blind placebo controlled cross-over study of the antihypertensive effects of fenoldopam. Fenoldopam significantly increased baseline plasma renin activity (PRA); baseline plasma aldosterone levels rose slightly. Baseline PRL and the PRL response to metoclopramide were not altered by fenoldopam. After metoclopramide, a significant increase of plasma aldosterone was observed during treatment with fenoldopam, as well as in the placebo-period. The peak values were not significantly different and occurred at 15 min during both treatment periods. These results indicate that fenoldopam does not reduce metoclopramide-induced aldosterone secretion and therefore suggest that the adrenal dopamine receptor is not identical to the vascular DA1 receptor.
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PMID:Effect of fenoldopam on the aldosterone response to metoclopramide in man. 287 51

The effects of dopexamine on the renal circulation have been examined to show whether any augmentation of renal blood flow (RBF) was secondary to the effect of the drug on cardiac output (CO) or whether it had any additional direct renal vasodilator activity. Eight male patients with mild to moderate hypertension, who were undergoing renal vein catheterization for renin estimation, were studied. Dose related increments in RBF (baseline (B) = 504 ml X min-1; after treatment (D) = 605 ml X min-1), CO (B = 5.9 l X min-1; D = 6.7 l X min-1), heart rate (B = 77 beats/min; D = 100 beats/min) and systolic blood pressure (B = 143 mmHg; D = 166 mmHg) were observed on administration of dopexamine 3 micrograms X kg-1 X min-1, with insignificant changes in diastolic blood pressure (B = 84.4 mmHg; D = 90 mmHg) and total peripheral resistance (B = 17.85; D = 17.25 Units). There was a slight but significant reduction in renal vascular resistance (B = 20.59, D = 18.75). The ratio of RBF to CO (%) confirmed that the increase in RBF due to dopexamine hydrochloride was greater that attributable to the increase in CO or perfusion pressure alone (RBF/CO B = 8.5%, D = 9%), consistent with selective renal vasodilatation. The fall in renin activity and lack of systemic vasodilatation suggest that this was a DA1-receptor mediated effect.
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PMID:Human renovascular effects of dopexamine hydrochloride: a novel agonist of peripheral dopamine and beta 2-adreno-receptors. 288 13

In normotensive anesthetized rats, 15-min IV infusions of quinpirole (2.5-40.0 micrograms/kg/min) produced dose-related, rapidly appearing, and long-lasting decreases in mean carotid artery BP and HR. Hemodynamically, the hypotensive effects of quinpirole (10.0 micrograms/kg/min) were due to a fall in total peripheral vascular resistance inasmuch as CO did not undergo significant changes. Mesenteric, hindquarter, and renal blood flows were, respectively, reduced, unchanged, and increased by quinpirole; thus, the renal vascular resistance fell more than either the total peripheral or hindquarter vascular resistance. Biochemically, the hypotensive effects of quinpirole were accompanied by a decrease in the plasma level of norepinephrine and plasma renin activity. The peak fall in blood pressure produced by quinpirole was not significantly modified by atenolol, idazoxan, ranitidine, SCH 23390 (DA1 dopamine receptor antagonist), enalapril, or SK&F 100273 (V1 vasopressin receptor antagonist), but was entirely blocked by S-sulpiride or removal of autonomic nerve drive to the cardiovascular system with chlorisondamine. The effect of quinpirole on systemic and regional vascular resistances was antagonized by S-sulpiride. Furthermore, SK&F 100273 prevented the fall in mesenteric flow produced by quinpirole. Intracerebroventricular injection of quinpirole (10.0 micrograms/kg over 2 min) in saline- or SK&F 100273-pretreated rats produced the same hypotensive effects as an identical IV dose of the compound. In pithed rats, quinpirole (10 micrograms/kg/min IV over 15 min) decreased pressor responses to electrical stimulation of spinal cord outflow without affecting those to exogenously injected angiotensin II, B-HT 920, cirazoline, norepinephrine, or 5-hydroxytryptamine. This inhibitory effect was antagonized by S-sulpiride. The bradycardia produced by quinpirole in intact rats was mediated by the autonomic nervous system inasmuch as it was slightly modified by bilateral vagotomy, partly reduced by atenolol, and entirely prevented by pithing even when the low HR of the last preparation had been raised by IV infusion of isoprenaline. Furthermore, S-sulpiride, but not SCH 23390 or idazoxan, antagonized this effect. In pithed rats, quinpirole similarly inhibited the tachycardic responses elicited by electrical stimulation of either the spinal cord outflow (preganglionic) or postganglionic cardioaccelerator nerve fibers. This effect of quinpirole was susceptible to S-sulpiride but not idazoxan blockade. Finally, in conscious spontaneously hypertensive rats (SHR) but not in normotensive rats, quinpirole (10 micrograms/kg/min IA over 15 min) lowered blood pressure.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Cardiovascular characterization of the DA2 dopamine receptor agonist quinpirole in rats. 289 67

Fenoldopam mesylate (SK&F 82526-J) is a novel benzazepine derivative. It has selective agonist activity at post-junctional (DA1) vascular dopaminergic receptors, which normally subserve renal artery vasodilation. Previous studies in normal subjects and in patients with hypertension indicate that fenoldopam increases renal blood flow and promotes a sodium diuresis. Drug efficacy was clinically evaluated in eight patients with chronic congestive heart failure (CHF) after a single oral dose of 100 mg of fenoldopam and following 3 days of therapy (100 mg four times daily). Stroke volume index acutely increased from 26 +/- 7 (mean +/- SD) to 30 +/- 4 ml/beat/m2 (p less than 0.05) and left ventricular filling pressure decreased from 26 +/- 13 to 23 +/- 11 mm Hg (p less than 0.05). Systemic vascular resistance decreased from 1513 +/- 159 to 1128 +/- 319 (p less than 0.05). Hemodynamic changes were seen as early as 30 minutes following fenoldopam and returned to control levels by 4 hours. Forearm blood flow, hepatic blood flow, and venous capacitance did not significantly change acutely, but renal blood flow index was significantly reduced (34 +/- 4 to 30 +/- 3 min-1 X 1000, p less than 0.01). Plasma norepinephrine, plasma renin activity, plasma arginine vasopressin, and plasma aldosterone did not significantly change acutely. After 3 days of treatment, 100 mg of fenoldopam again reduced the renal blood flow index (35 +/- 7 to 26 +/- 7 min-1 X 1000, p less than 0.01) and tended to increase plasma renin activity (11.7 +/- 8 to 21.2 +/- 19.4 ng/ml/hr, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hemodynamic, renal, and neurohumoral effects of a selective oral DA1 receptor agonist (fenoldopam) in patients with congestive heart failure. 289 70

1. gamma-L-glutamyl-L-dopa (gludopa) was given by intravenous infusion to six healthy salt-replete men on two occasions, with and without pretreatment with (+)-sulpiride. 2. Gludopa increased sodium excretion, glomerular filtration rate and effective renal plasma flow whilst decreasing plasma renin activity. 3. (+)-sulpiride had no significant effect on baseline natriuresis, renal haemodynamics or plasma renin activity, but significantly attenuated the rise in sodium excretion, glomerular filtration rate and effective renal plasma flow produced by gludopa. 4. (+)-sulpiride abolished the acute fall in plasma renin activity seen with gludopa. 5. (+)-sulpiride raised serum prolactin concentration but did not affect the ris in urine dopamine excretion rate caused by gludopa. 6. Gludopa exerts its renal effects by stimulating specific dopamine receptors which are principally of the DA1 subtype.
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PMID:(+)-sulpiride antagonises the renal effects of gamma-L-glutamyl-L-dopa in man. 312 7

8 beta-[(Methylthio)methyl]-6-propylergoline (pergolide) is a new, potent, long-acting dopaminergic DA2 receptor agonist currently being investigated for therapeutic use in patients with hyperprolactinemia, acromegaly or Parkinsons's disease. Since the influence of bromocriptine, a well-established dopaminomimetic compound, on aldosterone responsiveness and plasma renin activity is still a matter of debate, the efficacies of both compounds on these parameters and on kidney function, blood pressure, catecholamine release and prolactin levels were compared in 16 patients with prolactinoma. Supine and furosemide (40 mg i.v.)-stimulated plasma renin activity and aldosterone levels were similarly decreased by bromocriptine (2.5-30 mg/d) and pergolide (50-500 micrograms/d). Suppression of blood pressure, inhibition of stimulated norepinephrine release, increase in creatinine clearance, and decrease in base-line prolactin levels were similarly pronounced during treatment with both compounds. Metoclopramide (10 mg i.v.)-induced stimulation of aldosterone and prolactin levels, however, were suppressed only by bromocriptine and not by pergolide. It remains to be studied whether this difference between bromocriptine and pergolide is due to a potential agonist effect of pergolide on dopaminergic DA1 receptors which are influenced by bromocriptine in an antagonistic manner, or whether pergolide can be more readily displaced from its receptors than bromocriptine.
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PMID:Dopaminergic effects on kidney function and responsiveness of aldosterone, plasma renin activity, prolactin, catecholamines, and blood pressure to stimulation in patients with prolactinoma. Comparison of the efficacy of pergolide and bromocriptine therapy. 328 38


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