الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
ICC are specialized mesenchyme-derived cells that regulate contractility and excitability of SMCs. The distribution of ICC throughout the musculature of GIT is associated with nerve structures.
They show different distribution pattern and morphological features depending on their anatomical locations, accordingly they are classified into several subtypes.Some subtypes of ICC act as pacemakers of SMCs contraction . Ion channels reported as important points in the generation of pacemaker activity include non-selective cation channels,calcium-activated chloride channels while other subtypes of ICC are implicated in the modulation of enteric neurotransmission.
The current methods for ICC identification rely on a combination of ultrastructural characteristics as defined by TEM and immunohistochemistry with antibodies to tyrosine kinase receptor (c-kit).
It was found that c-kit signaling is needed for subsequent development
of ICC morphology and function, and maintenance of the ICC
phenotype after birth.
The studies reported marked decreaseof ICC number in normal human stomach and colon with age. These decreases are substantial and occur in both men and women.
The presence of ICLCs had been demonstrated in most visceral organs which generate spontaneous rhythmic muscle contractions e.g. the urinary and genital system .Their physiological role is still to be defined.
Knowledge of the importance of ICC for the integrity of the motor function of the GIT prompted interest in the fate of ICC in gut motor disorders. Damage to ICC and/or reduction of its population had been described in almost every gastrointestinal motility disorder from the esophagus to the rectum. There is already a significant evidence for the involvement of ICC in the pathophysiology of gastroparesis and constipation, but ICC abnormalities are also present in acquired conditions such as achalasia, Chagas disease, intestinal pseudo-obstruction, as well as congenital diseases such as HD and congenital hypertrophic pyloric stenosis . All these conditions exhibit abnormalities of motor activity leading to impaired regional transit.
ICC loss or disruption is associated often with concomitant neuronal and smooth muscle changes suggesting a close interdependence between them. It is still unclear for most of these motility disorders if the disruption in ICC networks is primary or secondary and it will be important to resolve this question.
The studies reported pathological changes of ICC in both Crohn’s disease and ulcerative colitis. These changes may explain the development of dysmotility in these diseases.
The studies reported that many GISTs are positive for c-kit and CD34 and have other features similar to those of ICC.
Knowledge on the role of ICC in gastrointestinal disorders is increasing. However, with the exception of GISTs, no major breakthrough had been made in treatment. Further studies may provide new treatments.
The distributon of ICLCs is impaired in certain disorders as UPJ obstruction and tubal ectopic pregnancy .The role of ICLCs in these disorders is still under study .