Huizinga J D, Golden C M, Zhu Y, White E J
Intestinal Disease Research Programme, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Neurogastroenterol Motil. 2004 Apr;16 Suppl 1:106-11. doi: 10.1111/j.1743-3150.2004.00484.x.
Interstitial cells of Cajal (ICC) are involved in generation of gut pacemaker activity, neurotransmission and stretch sensation. Pacemaker ICC exhibit spontaneous cyclic calcium oscillations that are in synchrony with its pacemaker activity. The spontaneous rhythmic inward currents in ICC that underlie gut pacemaker activity are linked to this calcium oscillation. It is probable that more than one type of channel contributes to the inward current with a high conductance chloride channel and a nonselective cation channel being the main candidates. The activation of these channels is linked to intracellular calcium cycling mechanism and involves inositol 1,4,5-trisphosphate (IP3)-mediated calcium release from the sarcoplasmic reticulum, and calcium uptake into mitochondria. This ion channel activity is modulated by signalling through neurotransmitter receptors, including the NK1 receptor. This finding and the presence of other neurotransmitter receptor mRNA transcripts indicates that ion channels in ICC are targets for neurotransmitter action. The ether-a-go-go-related (ERG) K channel is probably the most important K channel contributing to the resting membrane potential and excitability of the ICC. Many ion channels in ICC are regulated by second messenger systems which makes them highly susceptible to neurotransmitter modulation.
Cajal间质细胞（ICC）参与肠道起搏活动的产生、神经传递和牵张感觉。起搏ICC表现出自发性周期性钙振荡，与其起搏活动同步。构成肠道起搏活动基础的ICC中的自发性节律性内向电流与这种钙振荡相关。可能不止一种类型的通道对内向电流有贡献，其中高电导氯通道和非选择性阳离子通道是主要候选者。这些通道的激活与细胞内钙循环机制相关，涉及肌醇1,4,5-三磷酸（IP3）介导的钙从肌浆网释放以及钙摄取到线粒体中。这种离子通道活性通过神经递质受体的信号传导进行调节，包括NK1受体。这一发现以及其他神经递质受体mRNA转录本的存在表明，ICC中的离子通道是神经递质作用的靶点。醚-去极化相关（ERG）钾通道可能是对ICC静息膜电位和兴奋性贡献最大的钾通道。ICC中的许多离子通道受第二信使系统调节，这使得它们极易受到神经递质的调节。
