Premium
Slow excitatory synaptic transmission mediated by P2Y 1 receptors in the guinea‐pig enteric nervous system
Author(s) -
Hu H.Z.,
Gao N.,
Zhu M. X.,
Liu S.,
Ren J.,
Gao C.,
Xia Y.,
Wood J. D.
Publication year - 2003
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1113/jphysiol.2003.041731
Subject(s) - excitatory postsynaptic potential , myenteric plexus , purinergic receptor , neurotransmission , enteric nervous system , biology , electrophysiology , neuroscience , postsynaptic potential , inhibitory postsynaptic potential , endocrinology , receptor , adenosine , biochemistry , immunohistochemistry , immunology
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 P2Y 1 receptors on morphologically identified neurones in the submucosal plexus of guinea‐pig small intestine. MRS2179, a selective P2Y 1 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 P2Y 1 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 Ca 2+ from intracellular stores.