ASSESSMENT OF EFFICACY OF POLAPREZINC SUPPOSITORIES AGAINST RADIATION-INDUCED RECTAL DISORDERS USING AN EXPERIMENTAL RAT MODEL

Abstract

Purpose/Objective: To establish an experimental rat model and examine the efficacy of polaprezinc suppositories against radiation-induced rectal disorders. Materials/Methods: Female Wister rats (6 weeks old) were used in the present study. The rats were divided into three groups. Group A was irradiated and medicated with polaprezinc suppositories. Group B was irradiated without any medication. Group C had no irradiation or medication. The rat was taped by the tail in the vertical position under anesthesia. Lead shielding was used to cover the rats except the area of the lower pelvis. They were irradiated at 22 Gy by a single fraction. Polaprezinc suppositories were inserted daily into the rat anus for 7 days after irradiation. All rats were evaluated by colonoscopy on the 7th day after irradiation, sacrificed on the 10th day, and evaluated for mucosal damage. Results: In the clinical findings, the endoscopic findings, and the histological findings, the rats not administered polaprezinc suppositories tended to show more severe mucosal damage but there were no significant differences. Conclusion: Our study showed that this model was a useful experimental rat model for radiation-induced rectal disorders and polaprezinc suppositories demonstrated good efficacy against radiation proctitis.