维甲酸对大肠粘膜细胞增殖力学变化的影响

Effect of Retinoic Acid on Cell Proliferation Kinetics of Large Bowel Mucosa

通过应用维甲酸对大鼠大肠癌的诱发过程进行干预治疗，旨在观察维甲酸对大肠粘膜细胞增殖力学变化的影响。结果显示，维甲酸治疗组（Ⅱ组）大肠癌的发生率显著低于未加维甲酸治疗的对照组（Ⅰ组）。在诱癌的中晚期ＰＣＮＡ指数及ＡｇＮＯＲ数亦显著低于Ⅰ组（Ｐ＜０．０１）。Ⅰ、Ⅱ组的ＰＣＮＡ指数和Ａｇ－ＮＯＲ数显著高于未用诱癌剂的Ⅲ、Ⅳ组（Ｐ＜０．０１）。组内对比结果显示，Ⅰ组ＰＣＮＡ指数和ＡｇＮＯＲ数有随着诱癌时间延长而增加的趋势，差异有显著性（Ｐ＜０．０５），而Ⅱ、Ⅲ、Ⅳ组内比较差异无显著性（Ｐ＞０．０５）。本组结果表明，维甲酸可完全或部分阻断实验性大肠癌的癌变过程，降低大肠癌的发生率。对临床应用维甲酸预防和治疗大肠癌提供了有意义的资料。

To assess the interference of retinoic acid (RA)on cell proliferation kinetics of rat large bowel mucosa during colorectal carcinogenesis induced by DMH, both the expressions of proliferating cell nuclear antigen (PCNA)and nucleolar organizer region associated protein (AgNOR)were studied. The results showed that the prevalence of colorectal cancer was significantly lower in RA treated group (group Ⅱ)than in the untreated group (group Ⅰ)( P <0.05). The PCNA indices and mean AgNOR count in group Ⅱ were also significantly lower than those in group Ⅰ( P <0.01). The PCNA indices and mean AgNOR count in group Ⅰ, group Ⅱ were significantly higher than in the groups in which carcinogen was not used (group Ⅲ, group Ⅳ)( P <0.01). The results also showed that there was a tendency in group Ⅰ that the longer the interval induced by DMH the higher the PCNA index and AgNOR count expressed would be,however,there were no significant differences in between groups Ⅱ,Ⅲ and Ⅳ group ( P >0.05). It is therefore concluded that RA can inhibit the effect of DMH and decrease the incidence of colorectal cancer.