EFFECTS OF BTHP ON ACTION POTENTIAL OF TOAD SCIATIC NERVES / 中国药理学通报

ABSTRACT

Benzyltetrahydropalmatine ( BTHP ) which is a derivative of tet-rahydropalmatine, induced concentration-dependent decreases of the APA & dV/dt max and prolongation of conduction delay (CD) in toad sciatic neural action potential while it has little effect on APD.Bloocking action of Na+ -channel was measured with the dose required to produce 50% diminution of the value of APA, ie,EC50. EC50 of BTHP was 2.8 folds less than that of lidocaine and 11.9 folds more than that of quinidine, reflecting blocking action of Na+ -channel by BTHP, lidocaine, quinidine respectively.