Expression of the P2Y1Nucleotide Receptor in Chick Muscle: Its Functional Role in the Regulation of Acetylcholinesterase and Acetylcholine Receptor

摘要: In vertebrate neuromuscular junctions, ATP is stored at the motor nerve terminals and co-released with acetylcholine during neural stimulation. Here, we provide several lines of evidence that synaptic can act as a synapse-organizing factor to induce expression acetylcholinesterase (AChE) receptor (AChR) in muscles, mediated by metabotropic subtype, P2Y1 receptor. The activation P2Y1receptor adenine nucleotides stimulated accumulation inositol phosphates intracellular Ca2+ mobilization cultured chick myotubes. mRNA chicken muscle very abundant before hatching again increases adult. protein shown be restricted junctions colocalized AChRs adult (chicken, Xenopus , rat) but not embryo. chicks after hatching, this localization develops over ∼3 weeks. Denervation or crush (in caused up 90% decrease transcript, which was restored on regeneration, whereas AChR greatly increased. Last, mRNAs encoding AChE catalytic subunit α-subunit were induced when receptors activated specific agonists overexpression myotubes; those likewise activity myotubes promoter–reporter gene constructs for subunits, actions blocked P2Y1-specific antagonist. These results novel function regulating two postsynaptic effectors.