J Neurogastroenterol Motil.  2013 Oct;19(4):426-432.

Ionic Conductance(s) in Response to Post-junctional Potentials

• Koh SD
• Rhee PL

Abstract

The gastrointestinal motility is regulated by extrinsic and intrinsic neural regulation. Intrinsic neural pathways are controlled by sensory input, inter-neuronal relay and motor output. Enteric motor neurons release many transmitters which affect post-junctional responses. Post-junctional responses can be excitatory and inhibitory depending on neurotransmitters. Excitatory neurotransmitters induce depolarization and contraction. In contrast, inhibitory neurotransmitters hyperpolarize and relaxe the gastrointestinal smooth muscle. Smooth muscle syncytium is composed of smooth muscle cells, interstitial cells of Cajal and platelet-derived growth factor receptor alpha-positive (PDGFRalpha+) cells (SIP syncytium). Specific expression of receptors and ion channels in these cells can be affected by neurotransmitters. In recent years, molecular reporter expression techniques are able to study the properties of ion channels and receptors in isolated specialized cells. In this review, we will discuss the mechanisms of ion channels to interpret the post-junctional responses in the gastrointestinal smooth muscles.

Keyword

Gastrointestinal motility; Ionic conductance; Post-junctional potentials

MeSH Terms

Gastrointestinal Motility
Giant Cells
Interstitial Cells of Cajal
Ion Channels
Motor Neurons
Muscle, Smooth
Myocytes, Smooth Muscle
Neural Pathways
Neurotransmitter Agents
Receptors, Platelet-Derived Growth Factor
Ion Channels
Neurotransmitter Agents
Receptors, Platelet-Derived Growth Factor