Stimulatory effects of pituitary adenylate cyclase-activating polypeptide on inositol phosphates accumulation in avian cerebral cortex and hypothalamus.
This study has demonstrated that the short and long form of the pituitary adenylate cyclase-activating polypeptide (PACAP), i.e. PACAP(27) and PACAP(38), moderately but significantly, and in a concentration (0.5-5 microM)-dependent manner, stimulated inositol phosphates (IPs) accumulation in myo-[(3)H]inositol-prelabeled cerebral cortical and hypothalamal slices of chick and duck, and in slices of rat cerebral cortex; both peptides had no effect on IPs formation in rat hypothalamus. Vasoactive intestinal peptide (VIP; 0.5-5 microM) weakly enhanced IPs accumulation in chick hypothalamus, had no significant action in chick cerebral cortex (in fact there was a tendency to attenuate the IPs response in this tissue), and slightly, but significantly, inhibited the IPs accumulation in rat cerebral cortex. VIP showed no activity in rat hypothalamus. It is concluded that the stimulatory action of PACAP on phosphoinositide metabolism in avian cerebral cortex, similar to rat cerebral cortex, is mediated via phospholipase C-linked PAC(1) type receptors. In chick hypothalamus, however, there may be a component of VPAC type receptors stimulating IPs formation.
Nowak
Jerzy Z
JZ
Department of Biogenic Amines, Polish Academy of Sciences, P.O. Box-225, 90-950 Lodz 1, Poland. jerzyn@amina1.zabpan.lodz.pl
Pigulowska
Aleksandra
A
Kuba
Katarzyna
K
Zawilska
Jolanta B
JB
D000818:Animals; D001717:Birds / Q000033:anatomy & histology / Q000378:metabolism*; D002540:Cerebral Cortex / Q000166:cytology / Q000201:enzymology*; D002645:Chickens; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004372:Ducks; D007031:Hypothalamus / Q000166:cytology / Q000201:enzymology*; D007295:Inositol Phosphates / Q000378:metabolism*; D008297:Male; D009474:Neurons / Q000166:cytology / Q000201:enzymology*; D009479:Neuropeptides / Q000378:metabolism* / Q000494:pharmacology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051381:Rats; D017208:Rats, Wistar; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D011979:Receptors, Pituitary Hormone / Q000187:drug effects / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism / Q000494:pharmacology
C495403:Adcyap1 protein, rat; D007295:Inositol Phosphates; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D011979:Receptors, Pituitary Hormone; D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP