Alterations of Cajal cell in colon of slow transit constipation mice

AIM: To establish an animal model of slow transit constipation and to investigate the relationship between interstitial cell of Cajal in colon and the pathophysiological changes in the model of slow transit constipation. METHODS: The mouse model was established by subcutaneous injection of morphine. According to period of morphine injected, the mice were divided into two groups: 2.5 mg/kg/per day × 30 d (n =15) and 2.5 mg/kg/per day × 45 d (n =15), and corresponding control groups were established by injecting the same dosage of 9 g/L sodium chloride solution. Fecal weight was recorded daily, and transit function of intestine was measured by activated charcoal suspension pushing test. The changes of interstitial cell of Cajal were observed by immunohistochemistry. RESULTS: Fecal weight daily in test group was less than control group (18.8±3.2 g vs 20.6±1.8 g, P 0.05). Intestinal transit rate in test group was lower than control group (45.3±1.5% vs 49.2±1.8%, P 0.05). Colon tissue c-kit cell’s area in test group was more decreased than that of control group (81.3±7.9 ten thousand μm vs 98.6±8.0 ten thousand μm, P 0.05). CONCLUSION: Daily fecal mass, intestinal transit ratio and the number of interstitial cells of Cajal are decreased in the mouse model of slow intestinal transit movement induced by morphine and have a positive correlation with period of morphine injected. Lin L, Xu HC, Zhang HJ, Hu YD, Lin Z, Zhao ZQ. Alterations of Cajal cell in colon of slow transit constipation mice. Shijie Huaren Xiaohua Zazhi 2004;12(9):2107-2110