Effect of ketanserin, an inhibitor of 5-HT2 receptors, on the aldosterone-stimulating action of metoclopramide.
To estimate the possible involvement of a peripheral serotonergic pathway in the mechanism of the aldosterone-stimulating effect of metoclopramide (M) the plasma aldosterone (PA), renin activity (PRA) and prolactin (PRL) response to M was studied in 6 normal subjects before and after administration of ketanserin (K), a pure, specific, and selective blocking agent of 5-hydroxytryptamine type 2 (5-HT2) receptors. With K preadministration the M-induced increase of PRL was similar to that observed in control conditions, in accordance with the specific and peripheral antiserotonergic action of the drug. K potentiated the PA and PRA elevation in response to M. These data suggest that the PA response to M is not related to M's agonist activity at the peripheral 5-HT2 receptors level. The results further indicate that K can induce an enhancement of the activity of renin-angiotensin-aldosterone system with an higher PRA and PA response to stimulatory action of M.
D000293:Adolescent; D000328:Adult; D000450:Aldosterone / Q000097:blood*; D006801:Humans; D007650:Ketanserin; D007700:Kinetics; D008297:Male; D008787:Metoclopramide / Q000494:pharmacology*; D010880:Piperidines; D011188:Potassium; D011388:Prolactin / Q000097:blood; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000502:physiology; D012083:Renin / Q000097:blood; D012702:Serotonin Antagonists
D010880:Piperidines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D000450:Aldosterone; D011388:Prolactin; D007650:Ketanserin; D012083:Renin; D008787:Metoclopramide; D011188:Potassium