ИСТИНА

In neuromuscular junctions ATP is known to be a comediator of acetylcholine (ACh). It is released from peripheral motor nerve endings along with ACh and then undergoes fast hydrolysis by ectonucleotidases in synaptic cleft. ATP acts both on its pre- and postsynaptic receptors of P2X and P2Y types and it`s most well-known effect is autoregulatory decrease of synaptic transmission via metabotropic P2Y receptors. Whether this effect will be preserved during prolonged presence of ATP in synaptic cleft remained unknown. In this study possible pre- and postsynaptic effects of ATP accumulation in synaptic cleft of neuromuscular junctions (due to ectonucleotidases inhibition and tonic application of exogenous ATP) were investigated.