Dopamine inhibits corticosteroid secretion in frog adrenocortical cells: evidence for the involvement of prostaglandins in the mechanism of action of dopamine.
We have investigated the possible involvement of arachidonic acid metabolites in dopamine-induced inhibition of adrenocortical steroidogenesis. Administration of dopamine (5 x 10(-5) M) for 20 min to perifused frog adrenal slices caused a marked reduction of the release of both prostaglandin E2 (PGE2) and 6-keto-PGF1 alpha, the stable metabolite of prostacyclin (PGI2). Dopamine also induced a significant inhibition of corticosterone and aldosterone secretion. A lag period of 20 min was observed between inhibition of prostanoid and corticosteroid releases. Prolonged dopamine infusion did not prevent the stimulatory effect of PGE1, PGE2 or arachidonic acid on corticosteroid secretion. These observations indicate that activation of dopaminergic receptors in adrenocortical cells is linked to an inhibition of arachidonic acid metabolism. Our data also suggest that the inhibitory effect of dopamine occurs at a step preceding arachidonic acid formation.
Morra
M
M
Laboratoire d'Endocrinologie Moléculaire, URA CNRS 650, Unité Affiliée à l'INSERM, Faculté des Sciences, Université de Rouen, Mont-Saint-Aignan, France.
Leboulenger
F
F
Homo-Delarche
F
F
Netchitalo
P
P
Vaudry
H
H
D000302:Adrenal Cortex / Q000166:cytology / Q000378:metabolism*; D000305:Adrenal Cortex Hormones / Q000378:metabolism*; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology; D001696:Biomechanical Phenomena; D004298:Dopamine / Q000494:pharmacology* / Q000502:physiology; D008297:Male; D011453:Prostaglandins / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D011895:Rana ridibunda
D000305:Adrenal Cortex Hormones; D001095:Arachidonic Acids; D011453:Prostaglandins; D016718:Arachidonic Acid; D004298:Dopamine