In pithed Wistar rats, Tezosentan dose-dependently inhibits the pressor effect of big ET-1 (P<0.001 at all doses). At the lowest dose tested of 1 mg/kg, Tezosentan inhibits the pressor effect of the various doses of big ET-1 by 50 to 80%. Tezosentan has no effect by itself on blood pressure in these pithed rats. Tezosentan is very effective in a rat model of acute renal failure. ET antagonists have been shown to prevent the vasoconstriction and the renal failure that follow acute renal ischemia in rats[1].
