Stimulatory effect of vasoactive intestinal peptide (VIP) on the secretory activity of dispersed rat adrenocortical cells. Evidence for the interaction of VIP with ACTH receptors.
VIP dose-dependently increased basal, but not submaximally ACTH (10(-10) M)-stimulated, aldosterone (ALDO) and corticosterone (B) secretion of dispersed rat capsular and inner adrenocortical cells, respectively. The maximal stimulatory effect (60-70% rise) was obtained with a VIP concentration of 10(-8) M. [4-Cl-D-Phe6,Leu17]-VIP, a VIP-receptor antagonist (VIP-A), and corticotropin-inhibiting peptide (CIP), an ACTH receptor antagonist (both 10(-6) M), completely annulled VIP (10(-8) M)-evoked rises in basal ALDO and corticosterone secretions. The ACTH (10(-10) M)-enhanced (about 5-fold) production of both hormones was completely reversed by CIP (10(-6) M) and only partially reduced (about -30%) by VIP-A (10(-6) M). The hypothesis is advanced that the weak secretagogue effect of VIP on dispersed rat capsular and inner adrenocortical cells may be due to its positive interaction with ACTH receptors.
Mazzocchi
G
G
Department of Anatomy, University of Padua, Italy.
Malendowicz
L K
LK
Nussdorfer
G G
GG
D000302:Adrenal Cortex / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000450:Aldosterone / Q000378:metabolism; D000818:Animals; D003345:Corticosterone / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D018043:Receptors, Corticotropin / Q000037:antagonists & inhibitors / Q000187:drug effects*; D018005:Receptors, Vasoactive Intestinal Peptide / Q000037:antagonists & inhibitors; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
D018043:Receptors, Corticotropin; D018005:Receptors, Vasoactive Intestinal Peptide; D014660:Vasoactive Intestinal Peptide; D000450:Aldosterone; D003345:Corticosterone