Effects of an oral prostaglandin E1 agonist on blood pressure and its determinants in essential hypertension.
Arachidonic acid metabolites such as prostaglandins of the E series have well-documented effects on blood pressure (BP). Recently, a stable analogue of prostaglandin E1 (misoprostol) became available for oral use in humans, being primarily indicated for prevention of peptic disease induced by cyclo-oxygenase inhibitors. We hypothesised that misoprostol would exert antihypertensive actions and therefore performed a randomised, placebo-controlled clinical trial in 15 essential hypertensives to characterise the effects of a 400 micrograms oral dose of misoprostol on BP and its haemodynamic, autonomic and biochemical determinants. There was a modest (from 105.3 +/- 2.7 to 101.9 +/- 2.7 mmHg, P = 0.006) decrease in mean arterial pressure 20 minutes after the dose, accompanied by a decrease in systemic vascular resistance and a compensatory rise in cardiac output and heart rate. Baroreflex gain was unaltered by misoprostol, as were plasma renin activity, catecholamines and chromogranin A. Even this transient antihypertensive effect was abolished by cyclooxygenase inhibitor pretreatment. We conclude that oral misoprostol exerts a modest but transient antihypertensive effect that is unlikely to be of either therapeutic benefit or concern in essential hypertension.
Kailasam
M T
MT
Department of Medicine, University of California, San Diego 92161.
Lin
M C
MC
Cervenka
J H
JH
Parmer
R J
RJ
Kennedy
B P
BP
Ziegler
M G
MG
O'Connor
D T
DT
D000284:Administration, Oral; D000328:Adult; D000959:Antihypertensive Agents / Q000494:pharmacology*; D017704:Baroreflex / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects*; D004347:Drug Interactions; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D007052:Ibuprofen / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D016595:Misoprostol / Q000494:pharmacology*
D000959:Antihypertensive Agents; D016595:Misoprostol; D007052:Ibuprofen