title: Effect of [4Cl-D-Phe6,Leu17]VIP on the inhibition of pulsatile LH release by VIP and related peptides in the ovariectomized rat.
abstract: Pulsatile LH secretion in the ovariectomized (OVX) rat is inhibited by intracerebroventricular (icv) infusion of vasoactive intestinal peptide (VIP). VIP, rat growth hormone-releasing hormone (rGRH) and secretin with and without an antagonist to VIP, [4Cl-D-Phe6,Leu17]VIP (VIPA), were infused icv into OVX rats. Both VIP and rGRH at an infusion rate of 3.5 nmol/h lowered mean LH concentrations and pulse frequency without affecting pulse amplitude, and these effects were blocked by concurrent infusion of VIPA (10.5 nmol/h). Secretin also inhibited pulsatile LH secretion, but was only fully effective at the higher infusion rate of 7 nmol/h. This effect of secretin was also blocked by concurrent infusion of 10.5 nmol/h of VIPA. These results suggest that all three of these peptide hormones inhibit pulsatile LH secretion by an interaction with VIP receptors.
authors: Department of Physiology, University of Western Ontario, London, Canada.
authors: R F
authors: RF
authors: Weick
authors: K M
authors: KM
authors: Stobie
authors: K A
authors: KA
authors: Noh
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology; D007276:Injections, Intraventricular; D007986:Luteinizing Hormone / Q000378:metabolism*; D010052:Ovariectomy; D010507:Periodicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012633:Secretin / Q000008:administration & dosage / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000494:pharmacology*
chemical_list: C048507:vasoactive intestinal peptide, 4-chloro-Phe(6)-Leu(17)-; D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D007986:Luteinizing Hormone; D013007:Growth Hormone-Releasing Hormone