TY - JOUR
T1 - Slow excitatory synaptic transmission mediated by P2Y1 receptors in the guinea-pig enteric nervous system
AU - Hu, H. Z.
AU - Gao, N.
AU - Zhu, M. X.
AU - Liu, S.
AU - Ren, J.
AU - Gao, C.
AU - Xia, Y.
AU - Wood, J. D.
PY - 2003/7/15
Y1 - 2003/7/15
N2 - Electrophysiological recording was used to study a type of slow excitatory postsynaptic potential (slow EPSP) that was mediated by release of ATP and its action at P2Y1 receptors on morphologically identified neurones in the submucosal plexus of guinea-pig small intestine. MRS2179, a selective P2Y1 purinergic receptor antagonist, blocked both the slow EPSP and mimicry of the EPSP by exogenously applied ATP. Increased conductance accounted for the depolarization phase of the EPSP, which occurred exclusively in neurones with S-type electrophysiological behaviour and uniaxonal morphology. The purinergic excitatory input to the submucosal neurones came from neighbouring neurones in the same plexus, from neurones in the myenteric plexus and from sympathetic postganglionic neurones. ATP-mediated EPSPs occurred coincident with fast nicotinic synaptic potentials evoked by the myenteric projections and with noradrenergic IPSPs evoked by sympathetic fibres that innervated the same neurones. The P2Y1 receptor on the neurones was identified as a metabotropic receptor linked to activation of phospholipase C, synthesis of inositol 1,4,5-trisphosphate and mobilization of Ca2+ from intracellular stores.
AB - Electrophysiological recording was used to study a type of slow excitatory postsynaptic potential (slow EPSP) that was mediated by release of ATP and its action at P2Y1 receptors on morphologically identified neurones in the submucosal plexus of guinea-pig small intestine. MRS2179, a selective P2Y1 purinergic receptor antagonist, blocked both the slow EPSP and mimicry of the EPSP by exogenously applied ATP. Increased conductance accounted for the depolarization phase of the EPSP, which occurred exclusively in neurones with S-type electrophysiological behaviour and uniaxonal morphology. The purinergic excitatory input to the submucosal neurones came from neighbouring neurones in the same plexus, from neurones in the myenteric plexus and from sympathetic postganglionic neurones. ATP-mediated EPSPs occurred coincident with fast nicotinic synaptic potentials evoked by the myenteric projections and with noradrenergic IPSPs evoked by sympathetic fibres that innervated the same neurones. The P2Y1 receptor on the neurones was identified as a metabotropic receptor linked to activation of phospholipase C, synthesis of inositol 1,4,5-trisphosphate and mobilization of Ca2+ from intracellular stores.
UR - http://www.scopus.com/inward/record.url?scp=0038116602&partnerID=8YFLogxK
U2 - 10.1113/jphysiol.2003.041731
DO - 10.1113/jphysiol.2003.041731
M3 - Article
C2 - 12807993
AN - SCOPUS:0038116602
SN - 0022-3751
VL - 550
SP - 493
EP - 504
JO - Journal of Physiology
JF - Journal of Physiology
IS - 2
ER -