RESUMO
In-vitro studies had shown that ketamine, thiopental and propofol attenuated endothelium-dependent vasodilatation in different species. In this study, the effect of intravenous anesthetics on endothelium-dependent and - independent vasodilatation was examined in intact rats. The effect of acetylcholine and sodium nitroprusside on mean arterial pressure [MAP] was examined in conscious and ketamine, thiopental, propofol and urethane anesthetized rats. MAP was significantly higher in ketamine-anesthetized rats than in conscious rats. There was no significant change in MAP in other anesthetized groups. Also, acetylcholine and sodium nitroprusside induced dose-dependent decrease in MAP in all groups. Ketamine and thiopental potentiated the vasodepressor effect of both acetylcholine and sodium nitroprusside in comparison to the conscious group. Propofol did not have any significant effect on the vasodepressor response to both acetylcholine and sodium nitroprusside. Urethane potentiated the effect of acetylcholine but not that of sodium nitroprusside induced vasodilatation. Ketamine and thiopental, but not propofol, potentiated both endothelium-dependent and independent vasodilatation in intact rats