一氧化氮在金黄地鼠颊囊粘膜癌变中的动态观察

The Dynamic Changes of Nitric Oxide Level Hamster Buccal Pouch Carcinogenesis

目的:探讨金黄地鼠颊囊粘膜癌变过程中血清及组织中一氧化氮的作用,为口腔癌的预防及早期诊断寻找 一个新的检测指标。方法:用二甲基苯并萘(DMBA)诱导金黄地鼠颊囊癌变,并在诱导癌变的不同阶段检测血清 中一氧化氮的浓度及组织中iNOS的表达。结果:地鼠颊囊粘膜在由正常向鳞癌发展的过程中,血清NO浓度及组 织中iNOS的表达强度均呈上升趋势,鳞癌组血清NO浓度与正常粘膜组、单纯增生组、异常增生组相比均有显著性 差异(P<0.05);免疫组化显示,正常颊囊粘膜组织中未见iNOS阳性表达,鳞癌中iNOS的表达较单纯增生时显著 增强(P<0.01)。血清NO浓度与组织中iNOS的表达强度之间存在正相关关系(rB=0.590,P<0.01)。结论:一 氧化氮在口腔粘膜鳞癌的发生、发展中起着促进作用,可作为诱癌过程中的一个判断指标。

Objective: To assess the role of nitric oxide in the golden hamster pouch carcinogenesis induced by 7,12-dim-ethylbenzanthracene( DMBA). Methods: Seventy-two outbred six-week old Syrian golden hamster were randomly divided into one experimental group (60 animals) and one control group (12 animals). The control group remained untreated. The pouches of the experimental group were painted with 0. 5% DMBA solution three times each week. Light microscope was used to observe the pathologic changes. The serum nitric oxide level was measured by chemical photometry. The expression activity of the inducible nitric oxide synthase was observed by immunohistochemistry. Results: In oral carcinoma group serum NO level and iNOS protein expression were significantly increased compared with the normal or hyperplasia group (P < 0. 05) , No iNOS protein expression could be detected in the untreated pouches. There was a significant relationship between iNOS protein expression and serum NO level (rs =0.590, P<0.01). Conclusion: Increased NO level could contribute to the mechanism for experimentally induced oral carcinogenesis.