PA-8

PA-8 is a small molecule receptor antagonist for PACAP Type I (PAC1) that is selective, effective, and orally active. PA-8 inhibits PacAP-induced CREB phosphorylation at PAC1- receptors, but does not inhibit VPAC1- or vpac2 receptors. PA-8 also inhibited PacAP-induced elevation of cAMP levels in vitro (IC50 = 2 nM) and PacAP-induced aversive response and mechanical atopic pain after intrathecal injection in vivo.