OBJECTIVETo investigate the association of expression of c-kit (marker of interstitial cells of Cajal, ICC) in colon with slow transit constipation (STC) in rats.

METHODSSlow transit constipation (STC) rat model was induced by intragastric administration of compound diphenoxylate. Western blotting was used to measure the expression of c-kit in colon of STC rats (model group) and normal rats (control group). Gray scale ratio of c-kit to β-actin was used as the relative quantity of c-kit.

RESULTSFecal quantity per day of STC group was (1.3±0.7) g/100 g, significantly lower than that in normal rats [(1.6±0.9) g/100 g, t=10.798, P<0.05]. In model rats, the time of discharge of the first black fecal was (461.6±150.8) min, significantly longer than that in normal rats [(351.3±119.9) min, t=2.291, P<0.05]. Western blotting revealed that the average values of gray scale ratio of c-kit in proximal colon were 0.277±0.077 and 0.576±0.081 (t=10.719, P<0.05), in distal colon were 0.280±0.075 and 0.571±0.079 (t=10.700, P<0.05) in model group and control group respectively.

CONCLUSIONDown-regulation of c-kit expression in proximal colon and distal colon is associated to the pathogenesis of slow transit constipation in rats.