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Published on: January 18, 2011
Frequency-dependent effect of ethanol on action potentials of frog skeletal muscle fibers
1Department of Pharmacology, Faculty of Medicine, University of Alberta, Edmonton, Canada.
Abstract:
The effects of ethanol at the concentrations of 88 mM (0.5%) and 165 mM (1%) on single and repetitively elicited sodium action potentials were investigated in frog skeletal muscle fibers. At the concentrations used, although single action potentials remained intact, repetitively generated action potentials elicited with the stimulation frequency of 100 Hz for 2 sec were greatly inhibited. The inhibition of repetitively elicited sodium action potentials was completely reversed at 25 Hz. In conclusion, results indicate that ethanol inhibits sodium action potentials in a frequency-dependent manner.
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