Decrease in calcium currents induced by aminoglycoside antibiotics in frog motor nerve endings.

R S Redman; E M Silinsky

doi:10.1111/j.1476-5381.1994.tb16998.x

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Decrease in calcium currents induced by aminoglycoside antibiotics in frog motor nerve endings.

R S Redman·E M Silinsky

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Abstract

1. The effects of the aminoglycoside antibiotics, streptomycin, neomycin and gentamicin were examined on perineural currents and evoked acetylcholine (ACh) release at frog motor nerve endings. 2. In the standard solutions used previously to measure Ca2+ currents, streptomycin reduced the peak amplitude of the Ca2+ component of the perineural current. 3. In a solution in which changes in both Ca2+ currents and evoked ACh release can be recorded simultaneously, both Ca2+ currents and evoked ACh release were reduced by aminoglycosides in the potency order neomycin > streptomycin > gentamicin. This potency sequence is similar to that reported previously for these agents as inhibitors of neurally-evoked contractions of mammalian skeletal muscle. 4. These data suggest that the presynaptic inhibitory effects of aminoglycoside antibiotics at the neuromuscular junction occur as a consequence of a reduction in Ca2+ currents in the motor nerve terminal.

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Acetylcholine Animals Anti-Bacterial Agents Calcium Channel Blockers Electrophysiology Gentamicins In Vitro Techniques Motor Neurons Muscle, Skeletal Neomycin Nerve Endings Ranidae Streptomycin Tubocurarine Journal Article Research Support, U.S. Gov't, P.H.S.

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R S Redman, E M Silinsky. 1994. Decrease in calcium currents induced by aminoglycoside antibiotics in frog motor nerve endings.. https://doi.org/10.1111/j.1476-5381.1994.tb16998.x

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