Differential inotropic effects of halothane and isoflurane in dog ventricular tissues.
The differential effects of halothane (0.25-0.75%) and isoflurane (0.5-1.25%) on the electromechanical activity of canine ventricular tissues were compared in vitro. In Purkinje fibres, halothane but not isoflurane could induce an initial increase of contractile force which was not blocked by diltiazem or propranolol. In ventricular muscles, halothane decreased the resting state contraction more markedly than isoflurane. The results suggest that halothane induces a greater negative inotropy than isoflurane through a differential alteration of intracellular Ca2+ stores.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D004285:Dogs; D005260:Female; D006221:Halothane / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects; D007530:Isoflurane / Q000494:pharmacology*; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D011690:Purkinje Fibers / Q000187:drug effects
D007530:Isoflurane; D006221:Halothane