AJP - Heart and Circulatory Physiology, Vol 259, Issue 6 1674-H1680, Copyright © 1990 by American Physiological Society

ARTICLES

Hemodynamic and sympathetic effects of spinal administration of neuropeptide Y in rats

X. L. Chen, M. M. Knuepfer and T. C. Westfall
Department of Pharmacology, St. Louis University School of Medicine, Missouri 63104.

Intrathecal administration of 4 nmol/kg neuropeptide Y in Dial-urethane-anesthetized rats elicited decreases in arterial pressure, renal sympathetic nerve activity, and a slight decrease in heart rate. The depressor response was associated with a sustained hindquarters and mesenteric vasodilation resulting in a decrease in total peripheral resistance. Intrathecal NPY also resulted in a decrease in renal sympathetic nerve activity. There was a positive correlation between the percent changes in arterial pressure and renal sympathetic nerve activity. With the use of renal nerve activity and heart rate as indexes, NPY resulted in a decrease in baroreflex sensitivity. The depressor effect of intrathecal NPY did not appear to be due to spinal vasoconstriction and ischemia, since spinal microvascular resistance was decreased slightly. We conclude that the intrathecal administration of NPY produces an inhibition of sympathetic nerve activity, resulting in a decrease in total peripheral resistance and arterial pressure.

This article has been cited by other articles:

				M. Byku, H. Macarthur, and T. C. Westfall Nerve stimulation induced overflow of neuropeptide Y and modulation by angiotensin II in spontaneously hypertensive rats Am J Physiol Heart Circ Physiol, November 1, 2008; 295(5): H2188 - H2197. [Abstract] [Full Text] [PDF]