Cadmium inhibits stimulus-response coupling in skate (Raja erinacea) electric organ.
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.
Department of Pharmacology, State University of New York Health Science Center, Syracuse 13210.
O M
OM
Brown
J S
JS
Andrake
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D002118:Calcium / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D004557:Electric Organ / Q000187:drug effects* / Q000502:physiology; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D066298:In Vitro Techniques; D012860:Skates, Fish / Q000502:physiology*
D002104:Cadmium; D002794:Choline; D000109:Acetylcholine; D002118:Calcium