EFFICACY STUDIES OF CHEMOPREVENTIVE AGENTS IN ANIMAL MOD

本研究的目的是评估八种释放NO的NSAID减少或抑制结肠癌发生的功效，如通过使用根据下述两种方案处理的雄性Fisher 344大鼠的异常隐窝病灶测定所测量的。 根据Tudek、Bird和布鲁斯的方法，测量第一次接触致癌物前后的异常隐窝形成。 八周龄大鼠注射氧化偶氮甲烷（AOM）两次，每次15 mg/kg体重，间隔一周。 化学预防剂在第一次致癌物剂量后4周开始施用，并持续另外4周。 确定每个小肠和结肠的异常隐窝病灶的数量。此外，在低倍光学显微镜下测定未切片亚甲蓝染色组织中每个病灶的异常隐窝数量。 正在确定使用三种药剂的相对结肠癌化学预防功效，这三种药剂在隐窝测定中最有效。

The objective of the study is to assess the efficacy of eight NO-releasing NSAIDs to reduce or inhibit colon carcinogenesis as measured by the aberrant crypt foci assay using male Fisher 344 rats treated in accordance with the two protocols described below. Measure aberrant crypt formation before and after the first carcinogen exposure, according to methods of Tudek, Bird, and Bruce. Eight week old rats are injected twice with15 mg of azoxymethane (AOM) per kg of body weight one week apart. The chemopreventive agent is administered beginning at 4 weeks after the first carcinogen dose and for another four weeks. the number of aberrant crypt foci per small intestine and for colon are determined. Also the number of aberrant crypts per foci from unsectioned methylene-blue stained tissue under low power light microscopy are being determined. The relative colon cancer chemoprevention efficacy using the three agents are being determined which were most effective in the crypt assay.