This experimental study was performed for evaluate the effects of cis-di-amminedichloroplatinum(II) (cis-DDP) on the radiation injury of rat bowel by histopathologic changes.

Rats were exposed to entire abdomen by a single doses of X-ray(6-10 Gy) without or witn cis-DDP(2.5mg/kg). Rats were divided into 3 groups such as radiation alone, cis-DDP alone and combined group. In combined group, cis-DDP was given 30minutes before or immediately after irradiation.

Cis-DDP induced the inflammatory cell infiltrations with focal necrosis of the mucosa in the small bowel and no abnormal change in the large bowel. In radiation alone group, mucosal necrosis, subrnucosal fibrosis and muscular necrosis were prominent changes in small bowel and submucosal fibrosis in the large bowel. The submucosal fibrosis in the small bowel was appealed in 10 Gy of radiation alone group and 8 Gy of cis-DDP infusion after radiation and 6 Gy of cis-DDP infusion before radiation of combined group. In the large bowel, submucosal fibrosis was noted in 8 Gy of radiation alone group and 8 Gy of cis-DDP infusion after radiation and 6 Gy of cis-DDP infusion before radiation of combined group. In the small bowel, the enhancement ratio was 1.67 in a group of cis-DDP infusion before radiation and 125 in a group of cis-DDP infusion after radiation as the end point was the submucosal fibrosis,In the large bowel, the enhancement ratio was 1.33 in a group of cis-DDP infusion before radiation and 1.0 in a cup of cis-DDP infusion after radiation as e end point was e submucosal fibrosis.

This study suggested that cis-DDP enhance the radiation effect in the small and large bowel especially when cis-DDP was infused before radiation.