Cyclic AMP synchronizes evoked quantal release at frog neuromuscular junctions.

E Bukcharaeva; D Samigullin; E E Nikolsky; F Vyskocil

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PubMed · 11072809

Cyclic AMP synchronizes evoked quantal release at frog neuromuscular junctions.

E Bukcharaeva·D Samigullin·E E Nikolsky·F Vyskocil

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Abstract

At frog neuromuscular junction, noradrenaline (NA) shortens the release period for evoked quantal release acting on a beta1 receptor. To test the hypothesis that this action of NA is mediated by cAMP, we measured the latencies of focally recorded uni-quantal endplate currents (EPCs) after application of dibutyryl-cAMP (db-cAMP) and adenylyl cyclase activator, forskolin. The interval between the time when responses with minimal delay appeared and the point at which 90% of all latencies had occurred (P90 parameter) was shortened in the presence of both 1 x 10(-6) mol/l db-cAMP and 1 x 10(-6) mol/l forskolin by about 30%. The cAMP-induced shortening is equal to that found after application of NA and effects of both drugs are not additive.

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Acetylcholine Animals Cyclic AMP Electrophysiology Neuromuscular Junction Rana ridibunda Synaptic Transmission Time Factors Journal Article Research Support, Non-U.S. Gov't

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E Bukcharaeva, D Samigullin, E E Nikolsky, F Vyskocil. 2000. Cyclic AMP synchronizes evoked quantal release at frog neuromuscular junctions.. https://pubmed.ncbi.nlm.nih.gov/11072809/

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