Calcitonin gene-related peptide increases the expression of acetylcholinesterase in cultured chick myotubes.

Calcitonin gene-related peptide (CGRP), a neuropeptide may play a role in the formation of neuromuscular junctions is synthesized by the motor neurons and is able to stimulate the expression of acetylcholine receptor (AChR) in cultured myotubes. By using antibody and DNA probe that are specific for acetyl cholinesterase (AChE), we reported the expression of AChE could also be stimulated by CGRP in cultured chick myotubes. After CGRP application, the amount of AChE protein, that showed a molecular weight of approximately 105 kDa as recognized by the anti-AChE monoclonal antibody, was increased by approximately 1.7-fold. Two transcripts encoding AChE, approximately 4.8 and approximately 6.0 kb, were identified and their levels of expression were increased to approximately 3-fold after treatment with CGRP. However, the total AChE enzymatic activity in the CGRP-treated myotubes was unchanged. These evidences suggest that most of the CGRP-induced AChE proteins in the cultured chick myotubes are the inactive pool of enzyme.