Cadiovascular actions of central neuropeptide W in conscious rats

Abstract

Neuropeptide W(NPW) is a novel hypothalamic peptide that activates the orphan G protein-coupled receptors,GPR7 and GPR8.Two endogenous molecular forms of NPW that consist of 23- and 30-amino acid residues were identified. Although intracerebroventricular (i.c.v) administration of NPW is known to suppress spontaneouse-feeding at dark phase and fasting-induced food intake and to decrease body weight and plasma growth hormone, but to increase prolactin and corticosterone, little is known about its effect on other physiological functions. We examined the effects of i.c.v. administration of NPW30(0.3 and 3nmol) on mean arterial pressure (MAP),heart rate (HR),and plasma norepinephrine and adrenaline in conscious rats. NPW30 (3nmol) provoked increases in MAP (85.12±3.16 to 106.26±2.66 mm Hg) and HR (305.75±13.76 to 428.45±26.82 beats/min) and plasma norepinephrine and adrenaline. Intravenously administered NPW30 (3nmol) had no significant effects on MAP and HR. These results indicate that central NPW30 regulates sympathetic nervous outflow and affects cardiovascular function. [Jpn J Physiol 54 Suppl:S198 (2004)]