Effect of pinacidil on blood pressure, plasma catecholamines and plasma renin activity in essential hypertension.
Pinacidil, a new cyanoguanidine derivative, is an antihypertensive agent with arteriolar vasodilating properties, which acts on precapillary resistance vessels. A trial was carried out in 30 patients with essential hypertension WHO I-II. The treatment period was divided into three phases. Hydrochlorothiazide (HCTZ) and amiloride were administered for 4 weeks in Phase 1 and supine and standing blood pressure decreased significantly. During Phase 2 pinacidil was added to HCTZ/amiloride for the following 3 months. A further significant reduction in blood pressure was obtained. In the next period of treatment (Phase 3) patients were divided into two groups. For 1 month Group A (15 patients) received pinacidil alone and Group B (15 patients) received HCTZ/amiloride. Conventional laboratory blood tests in all patients remained unchanged during treatment. Reported side effects during Phase 2 were headache (2 patients), dizziness (3 patients), palpitations (2 patients) and ankle oedema (2 patients). Plasma renin activity was slightly increased at the end both of Phases 1 and 2. Plasma catecholamines were increased but not significantly at the end of Phase 2 as compared to Phase 1. The results indicate that pinacidil is effective in lowering blood pressure in mild to moderate essential hypertension.
D000328:Adult; D000368:Aged; D000584:Amiloride / Q000494:pharmacology / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects*; D001835:Body Weight; D002395:Catecholamines / Q000097:blood*; D002740:Chlorothiazide / Q000494:pharmacology / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D004837:Epinephrine / Q000097:blood; D005260:Female; D006146:Guanidines / Q000494:pharmacology* / Q000627:therapeutic use; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D020110:Pinacidil; D011897:Random Allocation; D012083:Renin / Q000097:blood*
D000959:Antihypertensive Agents; D002395:Catecholamines; D006146:Guanidines; D002740:Chlorothiazide; D020110:Pinacidil; D000584:Amiloride; D012083:Renin; D009638:Norepinephrine; D004837:Epinephrine