Gardiner S M, Compton A M, Bennett T, Palmer R M, Moncada S
Department of Physiology and Pharmacology, Medical School, Queen's Medical Centre, Nottingham, U.K.
Eur J Pharmacol. 1989 Nov 21;171(2-3):237-40. doi: 10.1016/0014-2999(89)90113-1.
Regional haemodynamic responses to endothelin-1 were assessed in conscious, unrestrained Long Evans rats, chronically instrumented with pulsed Doppler flow probes. Bolus injection of endothelin-1 (0.04 nmol) caused an early transient hypotension and increase in hindquarters vascular conductance. In the presence of NG-monomethyl-L-arginine (L-NMMA), which inhibits endothelial cell nitric oxide production, the hindquarters vasodilator response to endothelin-1 was unchanged and similar to that seen in the presence of vasopressin when the latter was infused to simulate the pressor effects of L-NMMA. These results indicate that the hindquarters vasodilatation in response to endothelin-1 is not dependent upon release of nitric oxide from endothelial cells.