Rapid desensitization of receptors for pituitary adenylate cyclase-activating polypeptide (PACAP) in chick cerebral cortex.
Pituitary adenylate cyclase-activating polypeptide (PACAP38) potently stimulates cyclic AMP formation in slices of chick cerebral cortex. One- to fifteen-minute pretreatment of slices with 30 nM PACAP38 led to a time-dependent attenuation (when compared with values observed in the control tissue) of the cyclic AMP response produced by subsequent re-stimulation with 1 microM PACAP38. Concentration-response curve for restimulation with PACAP38 applied at 0.01-1 microM to tissue slices preincubated for 15 min with 30 nM PACAP38 revealed dose-dependent decreases in subsequent cyclic AMP responses by 16-37%. It is concluded that in chick cerebral cortex, the receptors mediating PACAP-driven cyclic AMP responses (PAC1 receptors) undergo rapid homologous desensitization.
Niewiadomski
Paweł
P
Department of Biogenic Amines, Polish Academy of Sciences, POB-225, PL 90-950 Lódź, Poland.
Nowak
Jerzy Z
JZ
Sedkowska
Paulina
P
Zawilska
Jolanta B
JB
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D002645:Chickens; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D008297:Male; D009479:Neuropeptides / Q000494:pharmacology*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone / Q000819:agonists / Q000378:metabolism*
D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone; D000242:Cyclic AMP; D000262:Adenylyl Cyclases