Elucidation of the Vasoactive Intestinal Peptide Pharmacophore for VPAC₂ Receptors in Human and Rat and Comparison to the Pharmacophore for VPAC₁ Receptors

Abstract

Vasoactive intestinal peptide (VIP) functions as a neurotransmitter involved in a number of physiological and pathological conditions. The actions of VIP are mediated through VPAC 1 and VPAC 2 . In contrast to VPAC 1 , which has been extensively studied, little is known about the pharmacology of VPAC 2 . In this study we investigated the VIP pharmacophore for VPAC 2 by using alanine and D-amino acid scanning. We found significant species differences, and the human VPAC 2 (hVPAC 2 ) expressed in Chinese hamster ovary (CHO) cells,

VIP and PACAP analogs regulate therapeutic targets in high-risk neuroblastoma cells

“…This modification confers selectivity for PAC1/VPAC1 receptors because of a lower activation of VPAC2 receptors, as determined in transfected CHO cells expressing the human PAC1, VPAC1 or VPAC2 [35,47]. This suggests that, in Kelly cells, the effect of VIP is mediated by the VPAC1 receptor which binds VIP and PACAP while PAC1 is a PACAPspecific receptor.…”

Participation of vasoactive intestinal polypeptide in ovarian steroids production during the rat estrous cycle and in the development of estradiol valerate-induced polycystic ovary

“…A role for VIP/pituitary adenylate cyclase-activating peptide (PACAP) in follicular development has also been recently proposed from studies in mouse (Cecconi et al 2004). Since both peptides occupy the different VIP/PACAP receptor subtypes with the same affinity (Igarashi et al 2002), it is difficult to distinguish specific effects of VIP on the receptor population from PACAP effects. As such no measures of VIP receptors were undertaken.…”

Vasoactive intestinal peptide–camptothecin conjugates inhibit the proliferation of breast cancer cells

“…1). 125 I-VIP bound specifically to 3T3 cells stably transfected with VPAC 1 -R (total binding was 5057 ± 263 cpm and nonspecific binding was 225 ± 27 cpm) and VPAC 2 -R, whereas 125 I-Ro bound specifically to 3T3 cells stably transfected with VPAC 2 -R (total binding was 2945 ± 176 and nonspecific binding was 220 ± 107 cpm) but not VPAC 1 -R. Also, 125 I-VIP bound specifically to T47D breast carcinoma cells (total binding was 1127 ± 52 cpm whereas nonspecific binding was 68 ± 5 cpm), which have VPAC 1 -R [19], whereas 125 I-Ro bound with high affinity to SupT1 cells (total binding was 764 ± 39 cpm and nonspecific binding was 15 ± 1 cpm), which have VPAC 2 -R [21]. (Fig.…”

“…Binding was performed as described previously [21]. The standard binding buffer contained 24.5 mM HEPES (pH 7.4), 98 mM NaCl, 6 mM KCl, 5 mM MgCl 2 , 2.5 mM NaH 2 PO 4 , 5 mM sodium pyruvate, 5 mM sodium fumarate, 0.01% (w/v) soybean trypsin inhibitor, 1% amino acid mixture, 0.2% (w/v) bovine serum albumin (BSA), and 0.05% (w/v) bacitracin.…”

“…Cells were split weekly 1/20 with trypsin-EDTA. Balb 3T3 cells stably expressing human VPAC 1 -R or VPAC 2 -R were made as described previously [21] and were grown in DMEM supplemented with 300 mg/liter of G418 sulfate. Cells were mycoplasma free and were used when they were in exponential growth phase after incubation at 37°C in 5% CO 2 , 95% air.…”