INFLUENCE OF THE 2ND AND 3RD GRADE ABSTRA CTS FROM SCORPION-VENOM IN BUTHUS-MARTENSII KARSCH ON ACTION-POTENTIALS OF FAST-RESPONSE MYOCARDIOCYTES

AIM: To screen the active components of sodium channel blockade action from Buthus martensii Karsch (BMK) scorpion venom. METHOD: Myocardioc ytes of mice were cultured. Action potentials of fast response myocard iocytes were recorded. The effects of 22 contents of BMK scorpion veno m in a concentration of 3 mg . L(-1) were tested and compared with tha t of TTX 2.5 mg . L(-1), nimodipine (Nim) 3 mg . L(-1) and BaCl2 24.4 mg . L(-1). RESULTS: BMK-1 and other 19 contents significantly decreas ed depolarization parameters V-max, APA, OS, and MDP. which was simila r to that of TTX and different from that of Nim and BaCl2. CONCLUSION: The variations in the action potentials of fast response myocardiolcy tes indicated that 20 contents of BMK scorpion venom had sodium channe l blockade action.