Cellular localization, expression and regulation of neuropeptide Y in kidneys of hypertensive rats

Neuropeptide Y (NPY) is a key modulator of the autonomic nervous system pla ying pivotal roles in cardiovascular and neuronal functions. In this study, we assessed the cellular localization and gene expression of NPY in rat ki dneys. We also examined the relationship between NPY gene expression and re nin in two rat models of hypertension (two-kidney, one-clip renal hypertens ion (2K1C), and deoxycorticosterone-salt-induced hypertension (DOCA-salt)) characterized by a similar blood pressure elevation. In situ hybridization and immunohistochemistry, using anti-NPY or anti-C-flanking peptide of NPY (CPON) antibodies, showed that NPY transcript and protein were colocalized in the tubules of rat kidneys. During experimental hypertension, NPY mRNA w as decreased in both kidneys of the 2K1C animals, but not in the kidney of DOCA-salt rats. In 2K1C rats, renal NPY content was also decreased. The dif ference in NPY gene expression between 2K1C rats (a high renin model of hyp ertension) and DOCA-salt rats (a low renin model of hypertension) suggests that circulating angiotensin II plays a role in local renal NPY gene expres sion and that the elevated blood pressure per se is not the primary factor responsible for the control of NPY gene expression in the kidney. (C) 1999 Elsevier Science B.V. All rights reserved.