THE ACTION OF DILTIAZEM AND GALLOPAMIL (D600) ON CALCIUM-CHANNEL CURRENT AND CHARGE MOVEMENT IN MOUSE PURKINJE NEURONS

The dihydropyridines (DHP) receptor forms a high threshold L-type calc ium channel in various excitable cells. In skeletal and cardiac muscle cells, a DHP receptor antagonist blocks not only the voltage-gated ca lcium current but also immobilizes the charge movement linked to the r eceptor. The DHP receptor is also present in cerebellar Purkinje neuro ns. Previously, we showed that nifedipine immobilizes a part of the ch arge movement but has no effect on the calcium channel current recorde d in freshly dissociated mice Purkinje neurons. We report here the eff ect of other families of DHP receptor antagonists, benzothiazepines an d phenylalkylamines, on the physiological properties of this receptor in mouse Purkinje neurons. (C) 1998 Elsevier Science Ireland Ltd.