Interstitial cell of Cajal 3368365 224726786 2008-07-10T03:54:37Z 155.230.15.139 /* Frequency of ICC pacemaker cells */ <!-- Comment -->The '''Interstitial cell of Cajal''' (ICC) is a type of [[cell (biology)|cell]] found in the [[gastrointestinal tract]]. It serves as a pacemaker that triggers [[peristalsis|gut contraction]].<ref name=Sanders>{{cite journal |author=Sanders K, Koh S, Ward S |title=Interstitial cells of cajal as pacemakers in the gastrointestinal tract |journal=Annu Rev Physiol |volume=68 |issue= |pages=307–43 |year= |pmid=16460275 |doi=10.1146/annurev.physiol.68.040504.094718}}</ref> Many types of [[smooth muscle]] tissues have now been shown to contain ICC, but with few exceptions the function of these cells is not known and an area of active [[research]]. An international society (International Society for ICC, www.isicc.org) has recently been formed to provide a forum to discuss research in ICC in a variety of tissues. ==Role in slow wave activity== ICC serve as [[electricity|electrical]] pacemakers and generate spontaneous electrical [[slow wave threshold|slow waves]] in the gastrointestinal (GI) tract. Electrical [[slow wave threshold|slow waves]] spread from ICC to [[smooth muscle cell]]s and the resulting depolarization initiates [[calcium ion]] entry and contraction. Slow waves organize gut contractions into phasic contractions that are the basis for [[peristalsis]] and [[segmentation (biology)|segmentation]]. ==Frequency of ICC pacemaker cells== The frequency of ICC pacemaker activity differs in different regions of the GI tract:{{Fact|date=February 2007}} * 3 per minute in the [[stomach]] * 12 per minute in the [[duodenum]] * 10 per minute in the [[ileum]] * 3 per minute in the [[Colon (anatomy)|colon]] ICC also mediate neural input from [[bowels|enteric]] [[motor neuron]]s. Animals lacking ICC have greatly reduced responses to the [[transmitter]], [[acetylcholine]], released from excitatory [[motor neuron]]s, and to the [[cell signaling|transmitter]], [[nitric oxide]], released from [[inhibitory motor neuron]]s. Loss of ICC in [[disease]], therefore, may interrupt normal neural control of gastrointestinal (GI) contractions and lead to [[functional GI disorder]]s, such as [[irritable bowel syndrome]]. ICC also express mechano-sensitive mechanisms that cause these cells to respond to stretch. Stretching GI muscles can affect the [[resting potential]]s of ICC and affect the frequency of pacemaker activity. ICC are also critical in the propagation of electrical slow waves. ICC form a network through which slow wave activity can propagate actively. If this network is broken, then 2 regions of muscle will function independently. ==Pathology== ICCs are thought to be the cells from which [[gastrointestinal stromal tumour]]s (GISTs) arise.<ref>{{cite journal |author=Miettinen M, Lasota J |title=Gastrointestinal stromal tumors: review on morphology, molecular pathology, prognosis, and differential diagnosis |journal=Arch Pathol Lab Med |volume=130 |issue=10 |pages=1466–78 |year=2006 |pmid=17090188}}</ref> Also, abnormalities in the ICC network is one cause of [[chronic intestinal pseudo-obstruction]].<ref name=degiorgio>{{cite journal |author=De Giorgio R, Sarnelli G, Corinaldesi R, Stanghellini V |title=Advances in our understanding of the pathology of chronic intestinal pseudo-obstruction |journal=Gut |volume=53 |issue=11 |pages=1549–52 |year=2004 |pmid=15479666 |doi=10.1136/gut.2004.043968}} [http://gut.bmjjournals.com/cgi/content/full/53/11/1549 Full Text]</ref> ==Eponym== The interstitial cells of Cajal are named after [[Santiago Ramón y Cajal]],<ref>{{cite journal |author=Sanders K, Ward S |title=Interstitial cells of Cajal: a new perspective on smooth muscle function |journal=J Physiol |volume=576 |issue=Pt 3 |pages=721–6 |year=2006 |pmid=16873406 |doi=10.1113/jphysiol.2006.115279}}</ref> a [[Spanish people|Spanish]] [[pathologist]] and [[Nobel laureate]]. ==Brainstem== Analogous cells are found in the [[brainstem]], and are associated with [[Gaze (physiology)|gaze]].<ref name="pmid17229829">{{cite journal |author=Farshadmanesh F, Klier EM, Chang P, Wang H, Crawford JD |title=Three-dimensional eye-head coordination after injection of muscimol into the interstitial nucleus of Cajal (INC) |journal=J. Neurophysiol. |volume=97 |issue=3 |pages=2322–38 |year=2007 |month=March |pmid=17229829 |doi=10.1152/jn.00752.2006 |url=http://jn.physiology.org/cgi/pmidlookup?view=long&pmid=17229829}}</ref> ==References== {{reflist|2}} ==External links== * [http://www.physio.unr.edu/icc// Overview of ICCs] - unr.edu. * {{Dorlands|c_18|12223800}} {{Gastrointestinal physiology}} {{Mesencephalon}} {{cell-biology-stub}} {{digestive-stub}} {{neuroscience-stub}} [[pt:Célula intersticial de Cajal]]