Tissue-specific and developmental expression of pituitary adenylate cyclase-activating polypeptide (PACAP) receptors in rat brain.
The two forms of pituitary adenylate cyclase-activating polypeptide, PACAP27,and PACAP38, are novel members of the vasoactive intestinal peptide (VIP)/secretin/glucagon family of peptides. PACAP receptors that are positively coupled to adenylate cyclase and phospholipase C have been recently identified. We examined the expression of PACAP receptors in the rat cortex, hippocampus, cerebellum and hypothalamus during postnatal development. Functional studies revealed PACAP stimulation of cAMP formation in all the brain areas examined and [3H]inositol monophosphate ([3H]InsP) accumulation only in the cerebellum and hypothalamus. Throughout development, the efficacy or PACAP in stimulating cAMP formation slightly increased in the cortex and hypothalamus and decreased in the hippocampus and cerebellum; PACAP stimulation of [3H]InsP formation decreased in the cerebellum and remained steady in the hypothalamus. The effects of PACAP27 and PACAP38 on cAMP levels and inositol phospholipid hydrolysis were dose-dependent between 1 and 100 nM. In the same brain areas, treatment with VIP increased cAMP formation at doses greater than 100nM and failed to affect [3H]InsP content, thus suggesting the existence of type-1 PACAP receptors. The reverse transcription polymerase chain reaction (RT-PCR) was used to analyse the mRNA expression of type-1 PACAP receptor splice variants. PACAP receptor gene expression in the central nervous system was regulated in a developmental- and tissue-specific manner. The PACAP-R transcript was detected in all the brain areas examined whereas PACAP-R-hop mRNA ocurred only in the cerebellum and hypothalamus. The different expression profiles and functional properties of PACAP receptors in the developing rat brain suggest an involvement of PACAP in histogenesis, maturation and neurotransmission.
D'Agata
V
V
Institutes of Pharmacology and General Pathology, University of Catania Medical School, 95100 Catania, Italy.
Cavallaro
S
S
Stivala
F
F
Canonico
P L
PL
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001483:Base Sequence; D001921:Brain / Q000254:growth & development / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology; D002531:Cerebellum / Q000254:growth & development / Q000378:metabolism; D002540:Cerebral Cortex / Q000254:growth & development / Q000378:metabolism; D000242:Cyclic AMP / Q000096:biosynthesis; D004789:Enzyme Activation; D018507:Gene Expression Regulation, Developmental; D006624:Hippocampus / Q000254:growth & development / Q000378:metabolism; D007031:Hypothalamus / Q000254:growth & development / Q000378:metabolism; D007295:Inositol Phosphates / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D009479:Neuropeptides / Q000378:metabolism / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D009928:Organ Specificity; D010276:Parasympatholytics / Q000494:pharmacology; D010277:Parasympathomimetics / Q000494:pharmacology; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D011224:Prazosin / Q000494:pharmacology; D012326:RNA Splicing; D051381:Rats; D017207:Rats, Sprague-Dawley; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone / Q000096:biosynthesis* / Q000187:drug effects / Q000235:genetics; D013565:Sympatholytics / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism / Q000494:pharmacology
C495403:Adcyap1 protein, rat; D007295:Inositol Phosphates; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D010276:Parasympatholytics; D010277:Parasympathomimetics; 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; D013565:Sympatholytics; D014660:Vasoactive Intestinal Peptide; D001285:Atropine; D002217:Carbachol; D000242:Cyclic AMP; D010727:Phosphoric Diester Hydrolases; D000262:Adenylyl Cyclases; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D009638:Norepinephrine; D011224:Prazosin