Neuropeptide W-23(human) (NPW-23) is an endogenous ligand for NPBW1 and NPBW2.

NPW-23 increases the ICa,L in transfected human embryonic kidney 293 cells and VSMCs via GPR7 which may involve in the development of vascular hypertension. NPW-23 increases the expression of pan phospho-PKC, intracellular diacylglycerol level, and the second messenger catalyzed by PLC[1].

NPW-23 increases pressure-induced vasotone of the rat mesenteric arteries. Importantly, the expression of NPW is decreased in the hypertensive rats[1]. NPW-23 (0.3 nmol, 1.0 nmol, and 3.0 nmol) induces significant increases in mean arterial pressure (MAP) in conscious, freely moving male rats. Rats that receive either 1.0 or 3.0 nmol NPW-23 demonstrate a significant increase in total activity, ambulatory activity, and duration of stereotypy. NPW-23 fails to elevate MAP in rats pretreated with phentolamine. NPW-23-induced increases in total activity, ambulatory activity, and duration of stereotypy are reduced significantly by pretreatment with the orexin type 1 receptor (OX1R) antagonist, SB-408124 which suggests that orexin neurons are downstream targets of NPW [2].