Glushakov O. ATP-induced currents in the guinea-pig ileum submucous plexus neurons.

ATP-induced currents in the guinea-pig ileum submucous plexus neurons. -Manuscript. Thesis for a candidate of biological sciences by speciality 03.00.02-biophysics. -Bogomoletz Institute of Physiology, National Academy of Science of Ukraine, Kiev,1998. ATP-induced currents in submucous plexus neurons from the guinea-pig ileum were investigated using patch-clamp recordings in conventional and "perforated-patch" wholl-cell configurations. Exogenous ATP evoked two type fast-activated inward currents in most of the neurons and slow outward K+-currents in some neurons. It was established that submucous neurons expressed two distinct subtypes of ionotropic P2X-purinoceptors and metabotropic P2Y-purinoceptors. The physiological and pharmacological properties of the P2X-purinoceptors were investigated. The activity of nicotinic acethylcholine receptors (nAChRs) was decreased by activation of P2X-purinoceptors with ATP, which could not be explained by direct effect of ATP on nAChRs. It is suggested that this influence is due to a direct interaction between the P2X-purinoceptors and nAChRs. The results suggest that ATP may be a fast excitatory or slow inhibitory transmitter in synapses between submucous neurons. Key words: submucous neurons, patch-clamp, P2-purinoceptor, nicotinic acethylcoline receptor.