Table 1

Nomenclature of receptors for PACAP and VIP

Receptor subtype		Gene name (HUGO)	Human chromosome location	Selective agonists	Selective antagonist
IUPHAR nomenclature	Previous nomenclature	Gene name (HUGO)	Human chromosome location	Selective agonists	Selective antagonist
PAC₁	PACAP type I	ADCYAP1R1	7p14	Maxadilan	PACAP(6–38)^1-a
	PVR1
VPAC₁	VIP	VIPR1	3p22	[Arg¹⁶]chicken secretin^1-b	[Ac-His¹, d-Phe², Lys¹⁵, Arg¹⁶]
	VIP₁			[K¹⁵R¹⁶L²⁷]VIP(1–7)GRF(8–27)-NH₂	VIP(3–7)GRF(8–27)-NH₂
	PACAP type II
	PVR2
VPAC₂	VIP₂	VIPR2	7q36.3	Ro 25-1553	—
	PACAP-3			Ro 25-1392
	PVR3

↵1-a Displays significant affinity for VPAC₂receptors.
↵1-b Selective only in rodent tissues (e.g., brain) that do not express the secretin receptor.