A PACAP receptor agonist (IC50s = 4, 2, and 1 nM, respectively, for rat PAC1, rat VPAC1, and human VPAC2 recombinant receptors); binds to PACAP receptors in rat brain membrane (IC50 = 4.45 nM) and to SH-SY5Y and SK-N-MC human neuroblastoma and T47D human breast cancer cells (IC50s = 3.6, 13, and 4.7 nM, respectively); stimulates cAMP accumulation in H-SY5Y, SK-N-MC, and T47D cells (EC50s = 0.37, 0.26, and 0.73 nM, respectively); induces vasodilation of pial arterioles by 43% in newborn pigs (1 μM),