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Updated: Aug 12, 2026

Paradigms for Pharmacological Characterization of C. elegans Synaptic Transmission Mutants
Published on: August 18, 2008
Trifluoperazine and calcium antagonists accelerate cholinergic desensitization in Aplysia neurons
Abstract:
The onset of desensitization of excitatory acetylcholine responses in isolated, voltage clamped Aplysia RB neurons to microperfused agonist was accelerated by trifluoperazine and the calcium antagonists SKF-525A and D-600. In the absence of these drugs the time course of desensitization is described as the sum of two exponentials plus a constant. All 3 compounds accelerated the fast exponential component of desensitization, but had opposite effects on the slow component: trifluoperazine and SKF-525A accelerated the slow component, whereas this phase was greatly slowed by D-600. These results provide further evidence that the two components of cholinergic desensitization may be independent and influenced by agents which may affect calcium binding to the acetylcholine receptor.
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