Brown_1992_Comp.Biochem.Physiol.C_102_439

1. The effects of cadmium on stimulus-response coupling in the skate (Raja erinacea) electric organ were examined. 2. Cadmium decreased the evoked electrical discharge and the evoked release of 3H-ACh in a concentration-related fashion. 3. Cadmium (100 microM) also blocked voltage-dependent 45Ca uptake. 4. Both d-tubocurarine and nifedipine blocked Ca uptake and evoked potential, but not 3H-ACh release, thus most of the 45Ca uptake measured was post-synaptic through L Ca channels. 5. Nickel, cadmium, and verapamil inhibited 3H-ACh release and evoked potential, indicating a block of pre-synaptic T Ca channels.