Mechanism of action of serotonin on frog adrenal cortex.
The mechanism of action of serotonin (5-HT) on frog adrenal cortex has been investigated in vitro using the perifusion system technique. The direct effect of 5-HT on corticosteroid secreting cells was demonstrated, using enzymatically dispersed adrenocortical cells. Melatonin and 5-HTP appeared to be less potent than 5-HT to enhance corticosteroid secretion. In contrast Trp and 5-HIAA were totally devoid of effect on steroid secretion. To investigate the type of receptor involved in the stimulatory effect of 5-HT on adrenocortical cells, adrenal slices were stimulated with 5-HT in absence or presence of various antagonists. We observed that classical antagonists of 5-HT1, 5-HT2 and 5-HT3 type receptors failed to block 5-HT-induced corticosteroid secretion in our model. These results show that 5-HT exerts a direct effect on corticosteroid-secreting cells. Our data also indicates that the type of receptor involved in the action of 5-HT in frog adrenal cortex differs from mammalian 5-HT receptors.
Idres
S
S
Groupe de Recherche en Endocrinologie Moléculaire, URA CNRS 650, Université de Rouen, Mont-Saint-Aignan, France.
Delarue
C
C
Lefebvre
H
H
Larcher
A
A
Feuilloley
M
M
Vaudry
H
H
D006916:5-Hydroxytryptophan / Q000494:pharmacology; D000311:Adrenal Glands / Q000187:drug effects / Q000378:metabolism*; D000450:Aldosterone / Q000096:biosynthesis*; D000818:Animals; D003345:Corticosterone / Q000096:biosynthesis*; D006897:Hydroxyindoleacetic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D011895:Rana ridibunda; D012701:Serotonin / Q000494:pharmacology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D014364:Tryptophan / Q000494:pharmacology
D012702:Serotonin Antagonists; D012701:Serotonin; D000450:Aldosterone; D006897:Hydroxyindoleacetic Acid; D014364:Tryptophan; D006916:5-Hydroxytryptophan; D003345:Corticosterone