Effect Of Haloperidol And Sulpiride On Cardiac Electrophysiology Under Simulated Ischemic Conditions And Abnormal Potassium Concentrations

Objective: To observe the effects of different concentrations of Haloperidol (Hal) and Sulpiride (Sul) on action potentials rabbit cardiac conductive fibers and guinea pig cardiac papillary muscles under stimulatory ischemic conditions. To investigate of different concentrations of Haloperidol on action potentials rabbit cardiac conductive fibers exposed to abnormal extracellular potassium concentrations.Methods: By standard microelectrode technique, we observed the effects of Haloperidol on action potential parameters (APA, APD₉₀, V_max and ERP) of rabbit cardiac conductive tissues and guinea pig cardiac papillary cells, in which both tissues were simulated ischemic conditions. Also different concentrations of Haloperidol (0.1, 0.3, 1, 3, 10 μmol·L^-1) on action potentials rabbit cardiac conductive fibers under abnormal extra-cellular potassium concentrations.Results: different concentrations of Haloperidol (0.1, 0.3, 1, 3, 10 μmol·L^-1) were added to stimulatory ischemic perfusion tissues and a decrease in APA was observed. A significant prolongation of APD90 was detected when Hal was at 3 μmol·L^-1 and showed a concentration -dependency. Vmax was shortened concentration dependently and the changes were significant starting at 1μmol·L^-1.A concentration dependant increase in ERP was observed yet possessed no siginificancy. In guinea pig cardiac papillary muscles, all parameters were increased at 0.1μmol·L^-1 and decreased at 0.3 μmol·L^-1. Namely, the changes in APA, APD₉₀, V_max and ERP were significant when Hal concentrations were 0.1μmol·L^-1,1μmol·L^-1,0.3μmol·L^-1 and 1μmol·L^-1, respectively. Prior to Sul (1, 3, 10, 30,100, 300 μmol·L^-1) administration,...