Summary
Exposure of the frog neuromuscular junetion to cationized ferritin (200 μg ml−1) results in a reduction in MEPP frequency of approximately 25% within 10 min. This effect is not dependent on extracellular Ca2+, and identical results are obtained in salines buffered with EGTA. It is suggested that cationized ferritin does not inhibit transmitter release via a reduction in the intracellular Ca2+ concentration, but exerts its effect by a direct action on exocytosis. A mode of action is proposed.
Unlike Con A, cationized ferritin is unable to suppress the stimulation of spontaneous release caused by high osmolarity.
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Publicover, S.J. Inhibition of spontaneous transmitter release by the membrane ligand cationized ferritin. Naunyn-Schmiedeberg's Arch. Pharmacol. 318, 246–248 (1982). https://doi.org/10.1007/BF00500487
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DOI: https://doi.org/10.1007/BF00500487