Temperature Effect on Carbachol-Induced Depression of Spontaneous Quantal Transmitter Release in Frog Neuromuscular Junction

  title={Temperature Effect on Carbachol-Induced Depression of Spontaneous Quantal Transmitter Release in Frog Neuromuscular Junction},
  author={E. G. Strunsky and Mikhail Borisover and E. E. Nikolsky and Frantisek Vyskocil},
  journal={Neurochemical Research},
The effects of carbachol (CCh) on the frequency (f) of the miniature endplate potentials were tested at temperatures between 5 and 30°C. Higher CCh concentrations, 1 × 10−5 and 5 × 10−6 M, reduced the f to 60% and the temperature dependence was negligible. However, an inverse temperature dependence was found when low concentrations 3 × 10−7 and 6 × 10−7 M were applied. The depression of f was 40–50% in 5–10°C but only 10–20% of the control in the 25 and 30°C. During application of CCh, the new… 

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