Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study was made of the possible mechanisms underlying bupicomide- and hydralazine-induced increase of plasma renin activity. Six patients with mild to moderate hypertension were treated with both bupicomide and hydralazine on separate occasions in random order. Bupicomide lowered mean arterial pressure from 124.2 +/- 3.7 mm Hg (mean +/- SE) to 107.2 +/- 3.9 mm Hg (P less than 0.001). The associated increase in plasma renin activity was 1.27 ng/ml per hour and the increase in heart rate was 16.5 beats/min. Hydralazine reduced mean arterial pressure from 124.2 +/- 3.7 mm Hg to 107.0 +/- 2.0 mm Hg (P less than 0.01). The associated increase in plasma renin activity was 2.20 ng/ml per hour and the increase in heart rate was 22.4 beats/min. Plasma renin activity during bupicomide and hydralazine administration correlated positively with control plasma renin activity (r = 0.98, P less than 0.001). The log of plasma renin activity correlated positively with heart rate (r = 0.51, P less than 0.02) and negatively with mean arterial pressure (r = -0.62, P less than 0.005). We conclude that control plasma renin activity is a major determinant of change in plasma renin activity during administration of bupicomide or hydralazine. Both an increase in sympathetic activity and a decrease in perfusion pressure may contribute to the bupicomide- and hydralazine-induced increase in plasma renin activity, possibly by a baroreceptor-mediated increase in adrenergic tone.
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PMID:Physiologic mechanisms of bupicomide- and hydralazine-induced increase in plasma renin activity in hypertensive patients. 87 65

The cardiovascular effects of a new antihypertensive drug, bupicomide, were compared with those of hydralazine in 6 patients with mild to moderate hypertension. The mean supine arterial pressure of patients was reduced 15.2 mm Hg by bupicomide (900 to 2,000 mg/day) and 15.7 mm Hg by hydralazine (300 to 600 mg/day). Heart rate increased an average of 11.3 bpm during bupicomide and 14.5 bpm by hydralazine. Neither drug was associated with a postural decrease in mean arterial pressure. The heart rate response during maximum tolerated treadmill exercise was not diminished by either drug. Cardiac index was increased during administration of both drugs. Bupicomide and hydralazine reduced forearm vascular resistance, while renal blood flow and renal vascular resistance were not significantly modified. Evidence of equivalent augmentation of sympathetic nervous activity during administration of both drugs consisted of equal and significant increases in heart rate and urinary norepinephrine excretion, and decreases in duration of the pre-ejection period. The absolute values of these parameters were correlated with mean arterial pressure, which may indicate that the increase in sympathetic nervous activity was mediated by baroreceptor reflexes. Although bupicomide inhibits dopamine beta-hydroxylase, our results suggest that it is acting as a direct vasodilator.
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PMID:Antihypertensive effect of a dopamine beta hydroxylase inhibitor, bupicomide: a comparison with hydralazine. 109 50