目的　探讨诱导型一氧化氮合酶 (iNOS)与凋亡诱导基因p5 3、Bax蛋白在胆囊良恶性病变中的表达及相关意义。　方法　采用免疫组织化学SP法检测iNOS及p5 3、Bax蛋白在 16例慢性胆囊炎、11例慢性胆囊炎伴胆囊腺肌瘤增生及 2 4例胆囊腺癌中的表达。　结果　 1 在胆囊良恶性病变的胆囊壁中均有iNOS、Bax表达 ,在胆囊腺癌中iNOS、Bax表达下降 (P <0 0 5 ) ,p5 3仅在部分胆囊腺癌细胞核中有较强阳性表达 ;2 在胆囊良恶性病变中 ,iNOS与Bax表达呈正相关 (P <0 0 1) ,p5 3与Bax表达呈负相关 (P <0 0 1)。　结论　慢性胆囊炎尤其是慢性胆囊炎伴腺肌瘤增生是胆囊腺癌重要的危险因素 ,NO是重要中介分子 ,NO诱导胆囊良性病变恶变的作用与细胞凋亡有密切关系。 Objective To investigate the expression of inducible nitric oxide synthase (iNOS) and apoptosis-inducing genes p5 3 and Bax in gallbladder benign and malignant lesions and its significance. Methods Immunohistochemical SP method was used to detect the expression of iNOS, p53 and Bax protein in 16 cases of chronic cholecystitis, 11 cases of chronic cholecystitis with Gallbladder adenomyosis and 24 cases of gallbladder adenocarcinoma. Results 1 iNOS and Bax were expressed in the gallbladder wall of benign and malignant gallbladder lesions, while the expression of iNOS and Bax was decreased in gallbladder adenocarcinoma (P <0.05). The expression of p5 3 was only positive in some gallbladder adenocarcinoma (P <0.01). There was a negative correlation between the expression of p5 3 and Bax (P <0.01) in benign and malignant lesions of gallbladder. Conclusions Chronic cholecystitis, especially chronic cholecystitis with adenomyosis, is an important risk factor for gallbladder adenocarcinoma. NO is an important mediator. The role of NO in inducing gallbladder malignant transformation is closely related to apoptosis.