Objective To observe the influence of Shenqing Recipe (SQR)

a kind of Traditional Chinese Medicine

on the morphology and quantity of colonic interstitial cells of Cajal (ICC) in trinitrobenzene sulfonic acid (TNBS)-induced rat colitis

and to investigate the possible mechanism of SQR in regulating intestinal dynamics. Methods Sixty rats were randomly divided into normal control

model Ⅰ

model Ⅱ

mesalazine

and high-dose

and low-dose SQR groups with 10 rats in each group. TNBS (10 mg) dissolved in 50% ethanol was instilled into the lumen of the rat colon of the latter five groups to induce colitis. On the 4th day after administration of TNBS

each treatment group was administered one of the following formulations by enteroclysis gavage once a day for 7 days: 600 mg•kg-1•d-1 mesalazine

2.4 g•kg-1•d-1 SQR

and 1.2 g•kg-1•d-1 SQR. Model Ⅱ rats received normal saline solution. After 7 days colonic samples were collected. While the colonic samples of model Ⅰ group were collected on the 3rd day after TNBS administered. Ultrastructure of ICC in the damaged colonic tissues was observed with transmission electron microscope. Expression of c-kit protein in colonic tissue was determined by immunohistochemical staining and Western blot. Results The ultrastructure of colonic ICC in the rat model of TNBS-induced colitis showed a severe injury

and administration of SQR or mesalazine reduced the severity of injury. Similarly

the expression of c-kit protein of TNBS-induced colitis rat model was significantly decreased compared with the normal control group (P<0.05). Treatment with SQR or mesalazine significantly increased the expression of c-kit protein compared with the administration of control formulations (P<0.05)

especially the high-dose SQR group. Conclusion SQR could alleviate and repair the injured ICC

and improve its quantity

which might be involved in regulating intestinal motility.