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Updated: Jul 19, 2026

Loading a Calcium Dye into Frog Nerve Endings Through the Nerve Stump: Calcium Transient Registration in the Frog Neuromuscular Junction
Published on: July 8, 2017
Sr2+ induce a release of divalent cation from internal Ca2+ store by nerve stimulation at frog neuromuscular junction
1Daiichi Hoiku Junior College, Dazaifu, Fukuoka, Japan. e76141g@wisdom.cc.kyushu-u.ac.jp
Abstract:
The effects of Sr2+ on the transmitter release at the frog neuromuscular junction were examined electrophysiologically. The nerve trunk was stimulated by paired pulses at various time intervals after replacing extracellular Ca2+ by Sr2+, the paired-pulse facilitation at the 10 ms interval was smaller than that at 20-30 ms intervals. Administration of several intracellular Ca2+ mobilizers decreased the paired-pulse facilitation. These results suggest that the transmitter release in Sr2+ solution is caused, at least partly, by the release of divalent cations from the intracellular stores.
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