Effect of renal denervation on arterial pressure and renal norepinephrine concentration in Wistar-Kyoto and spontaneously hypertensive rats.

Renal norepinephrine (NE) concentration was measured at 2-week intervals after bilateral denervation of the kidneys in 5-week-old Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Sham-operated rats of both strains served as controls. Renal denervation significantly delayed but did not prevent the development of hypertension in SHR. Kidney NE concentration in renal-denervated SHR was 13, 25, 33, and 35% of that found in sham-operated SHR at 2, 4, 6, and 8 weeks, respectively, after denervation. Similarly, kidney NE concentration in renal-denervated WKY rats was 11, 24, 32, and 34% of controls but arterial pressure was not significantly altered. Renal-denervated SHR subjected to a second denervation operation 3 weeks after the initial operation continued to develop hypertension similar to those having only one operation. The results of this study support the hypothesis that renal nerves are involved in the hypertensive process in SHR during the early stages and suggest that renal reinnervation may occur within several weeks after denervation; however, the delayed rise in arterial pressure in renal-denervated SHR is not due to renal reinnervation.