Galligan J J
Department of Pharmacology and Toxicology, Michigan State University, East Lansing 48824, USA.
Tokai J Exp Clin Med. 1998 Jun;23(3):129-36.
The enteric nervous system can control gastrointestinal function independent of direct connections with the central nervous system. Enteric nerves can perform this task as there are multiple mechanisms of excitatory neurotransmission in enteric ganglia. There are two broad types of excitatory synaptic transmission, fast and slow excitatory synaptic responses. Fast excitatory postsynaptic potentials (fEPSPs) are recorded from "S" type neurons and some AH type neurons. S neurons are interneurons and motorneurons while AH neurons are intrinsic sensory neurons. Slow excitatory postsynaptic potentials (sEPSPs) can be recorded from some S neurons and also from AH type neurons. The fEPSPs recorded from S neurons and mediated largely by acetylcholine acting at nicotinic cholinergic receptors (nAChRs). However, ATP acting at P2X purine receptors contributes to the fEPSP in many S neurons. The fEPSPs recorded from AH neurons are also mediated largely by nAChRs but glutamate acting at AMPA receptors contributes to fEPSPs in some AH neurons. The sEPSPs in AH neurons are mediated by one or more neuropeptides and 5-hydroxytryptamine. The sEPSPs in AH neurons are due to inhibition of two types of resting potassium channels and activation of a chloride channel or a nonspecific cation channel. The multiple mechanisms of excitatory synaptic transmission in the enteric nervous system contribute to its capacity to regulate complex gastrointestinal functions.
肠神经系统能够独立于与中枢神经系统的直接连接来控制胃肠功能。肠神经能够执行此任务，因为肠神经节中存在多种兴奋性神经传递机制。兴奋性突触传递有两种主要类型，即快速和慢速兴奋性突触反应。快速兴奋性突触后电位（fEPSPs）是从“S”型神经元和一些AH型神经元记录到的。S神经元是中间神经元和运动神经元，而AH神经元是内在感觉神经元。慢速兴奋性突触后电位（sEPSPs）可从一些S神经元以及AH型神经元记录到。从S神经元记录到的fEPSPs主要由作用于烟碱型胆碱能受体（nAChRs）的乙酰胆碱介导。然而，作用于P2X嘌呤受体的ATP在许多S神经元中对fEPSP有贡献。从AH神经元记录到的fEPSPs也主要由nAChRs介导，但作用于AMPA受体的谷氨酸在一些AH神经元中对fEPSPs有贡献。AH神经元中的sEPSPs由一种或多种神经肽和5-羟色胺介导。AH神经元中的sEPSPs是由于两种静息钾通道受到抑制以及一种氯通道或一种非特异性阳离子通道被激活所致。肠神经系统中兴奋性突触传递的多种机制有助于其调节复杂胃肠功能的能力。
