Abstract
Electrophysiological investigation of the characteristics of ganglionic block by methylmercury (mHg) was carried out on the isolated superior cervical ganglion of the rabbit. A low concentration (5 μM) of mHg consistently produced a small increase in the amplitude of the compound action potential whereas an inhibitory effect was observed with higher concentrations (10–20 μM). The inhibitory effect was temperature-dependent and was not reversible by washing. Raising the external calcium concentration antagonized the inhibitory effect of mHg by markedly slowing down the progression of ganglionic block. The evidence indicates that the blocking effect of mHg is exerted principally on the presynaptic nerve terminals, and may be due to inhibition of acetylcholine release by interfering with the function of calcium at these terminals.
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Alkadhi, K.A., Taha, M.N. Antagonism by calcium of the inhibitory effect of methylmercury on sympathetic ganglia. Arch Toxicol 51, 175–181 (1982). https://doi.org/10.1007/BF00302758
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DOI: https://doi.org/10.1007/BF00302758