Pressor effect of NG-monomethyl-L-arginine in SHRSP.

Pressor effects of NG-monomethyl-L-arginine (L-NMMA), a selective inhibitor of nitric oxide production from L-arginine, on mean blood pressure (MBP) were investigated in conscious Wistar Kyoto rats (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP). L-NMMA (0.1-10 mg/kg, i.v.) elicited a dose-dependent increase in the MBP of WKY and SHRSP. The pressor response to L-NMMA was more marked in SHRSP than in WKY. These results suggest that nitric oxide may play an important role in the blood pressure regulation in the conscious SHRSP.