A novel depolarizing activity of scorpion venom fraction M1 due to activation of skeletal muscle nicotinic receptors

Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, Tunis BP 74-1002, Tunisia.
Toxicon (Impact Factor: 2.49). 02/2007; 49(1):117-22. DOI: 10.1016/j.toxicon.2006.09.011
Source: PubMed


A depolarizing activity following interaction with nicotinic acetylcholine receptors (nAchRs) in skeletal muscle cells, was observed for the first time in the non-toxic venom fraction (M1) of the yellow scorpion Buthus occitanus tunetanus (Bot). The effects of M1 fraction were tested on cultured rat myotubes by recording changes in [Ca2+]i. When applied, M1 (10 microg/mL) induced a transient increase of [Ca2+]i which could be blocked by a prior application of alpha-Bungarotoxin (alpha-Bg-Tx).

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