Acetylcholine-Induced Membrane Potential Oscillations
نویسندگان
چکیده
RESULTS. Acetylcholine (100 nM to 1 mM) induced a decrease in membrane conductance and a depolarization of membrane potential in the intact lens. The responses were reversed by application of the muscarinic antagonist, atropine (1 /xM to 100 /xM). In the presence of 1 JLLM thapsigargin and 30 JUM cyclopiazonic acid, acetylcholine still induced an electrical response. Long exposures to acetylcholine induced sustained oscillations of Vm in 10 of 29 lenses (34%). Oscillations were blocked by atropine and the L-type Ca channel blocker nifedipine (10 JUM) but were potentiated by thapsigargin.
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