Lack of effect of the serotonin4 receptor agonist zacopride on ACTH secretion in normal men.
OBJECTIVE
In the present study, we investigated the effect of zacopride on corticotropin (ACTH) and cortisol secretion in healthy volunteers. Male subjects received a single oral dose of placebo, 10 micrograms zaco-pride or 400 micrograms zacopride. Plasma ACTH, cortisol and aldosterone concentrations were measured before and during the 3 h following the administration of the drug.


RESULTS
For none of the doses did zacopride cause any modification of plasma ACTH or cortisol levels. In contrast, administration of 400 micrograms zacopride induced a significant increase in plasma aldosterone levels.


CONCLUSIONS
Our results indicate that in humans serotonin-evoked stimulation of ACTH secretion is not mediated through serotonin4 (5-HT4) receptors. Together with previous findings, these data indicate that the stimulatory effect of 5-HT4 receptor agonists on aldosterone secretion in man can be ascribed solely to a direct action on glomerulosa cells.
Lefebvre
H
H
Clinique Médicale et Endocrinologique, Hôpital de Boisguillaume, CHU de Rouen, France.
Contesse
V
V
Delarue
C
C
Kuhn
J M
JM
Vaudry
H
H
Wolf
L M
LM
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000328:Adult; D000450:Aldosterone / Q000097:blood*; D000704:Analysis of Variance; D001549:Benzamides / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D012702:Serotonin Antagonists / Q000494:pharmacology*
D001549:Benzamides; D019086:Bridged Bicyclo Compounds, Heterocyclic; D012702:Serotonin Antagonists; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; C055971:zacopride; D006854:Hydrocortisone