Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide stimulate two signaling pathways in CHO cells stably transfected with the selective type I PACAP receptor

C Delporte; P Poloczek; P de Neef; P Vertongen; E Ciccarelli; M Svoboda; A Herchuelz; J Winand; P Robberecht

doi:10.1016/0303-7207(94)03424-r

Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide stimulate two signaling pathways in CHO cells stably transfected with the selective type I PACAP receptor

Mol Cell Endocrinol. 1995 Jan;107(1):71-6. doi: 10.1016/0303-7207(94)03424-r.

Authors

C Delporte¹, P Poloczek, P de Neef, P Vertongen, E Ciccarelli, M Svoboda, A Herchuelz, J Winand, P Robberecht

Affiliation

¹ Laboratory of Biochemistry and Nutrition, Medical School, Université Libre de Bruxelles, Belgium.

PMID: 7796937
DOI: 10.1016/0303-7207(94)03424-r

Abstract

The properties of the pituitary adenylate cyclase activating polypeptide (PACAP) type I receptor were studied on a clone of Chinese hamster ovary cells (CHO) stably transfected with the recombinant receptor. PACAP(1-27), PACAP(1-38) and VIP inhibited [125I-acetyl-His1]PACAP (1-27) binding, stimulated cyclic AMP and inositol phosphates production and induced [Ca2+]i increase with the same order of potency: PACAP(1-27) = PACAP(1-38) > VIP. The concentrations required for half maximal receptor occupancy, IP3- and [Ca2+]i increase were not different for both PACAPs (1 nM) and 100-fold higher than those required for cyclic AMP increase (0.010 nM). These data suggest that the occupancy of a portion of the total receptors available was sufficient for maximal cyclic AMP production but not for maximal IP3 production. It is concluded that the possibility of the type I PACAP receptor being coupled to a transduction pathway is not located at the level of the ligand but rather at the level of the G-proteins.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adenylyl Cyclases / drug effects*
Animals
CHO Cells / drug effects
CHO Cells / metabolism
Calcium / metabolism
Cricetinae
Cyclic AMP / metabolism
Enzyme Activation / drug effects
GTP-Binding Proteins / physiology
Ligands
Neuropeptides / pharmacology*
Pituitary Adenylate Cyclase-Activating Polypeptide
Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide
Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
Receptors, Pituitary Hormone / classification
Receptors, Pituitary Hormone / genetics
Receptors, Pituitary Hormone / metabolism*
Recombinant Fusion Proteins / metabolism
Signal Transduction / drug effects
Transfection
Vasoactive Intestinal Peptide / pharmacology*

Substances

Ligands
Neuropeptides
Pituitary Adenylate Cyclase-Activating Polypeptide
Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide
Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
Receptors, Pituitary Hormone
Recombinant Fusion Proteins
Vasoactive Intestinal Peptide
Cyclic AMP
GTP-Binding Proteins
Adenylyl Cyclases
Calcium