血吸虫病兔直肠壁一氧化氮合成酶的免疫组化分析

Immunohistochemical observation of nitric oxide synthetase in rectum of rabbits infected with S. japonicum

目的研究一氧化氮（ＮＯ）在血吸虫直肠肉芽肿发病机制中的作用。方法采用腹部敷贴法建立血吸虫病兔模型，ＳＰ免疫组化法分析结构型和诱导型一氧化氮合成酶（ｃＮＯＳ和ｉＮＯＳ）在正常兔和血吸虫病兔直肠壁的表达与分布。结果正常兔直肠壁ｃＮＯＳ和ｉＮＯＳ呈阴性反应，血吸虫病兔直肠壁为强阳性，ｃＮＯＳ主要分布在粘膜毛细血管和粘膜下血管壁；ｉＮＯＳ不仅见于上述血管壁，而且见于虫卵、虫卵肉芽肿周围、纤维结缔组织中、炎性细胞之间。

Objective The objective of the study was to investigate the role of nitric oxide (NO) in the pathogenesis of rectum granuloma formation. Methods Rabbits were infected with cercaria of S. japonicum percutaneously. The SP immunohistochemical technique was used to analyse the expression and localization of cNOS and iNOS in the rectums of normal and schistosoma rabbits. Results Immunostaining of cNOS and iNOS were negative in the rectums of normal rabbits, whereas the results in the of rabbits infected with S. japonicum were strong positive. The positive immunostaining of cNOS was observed in mucosal capillaries and submucosal vessels. Besides in capillaries and submucosal vessels the positive immunostaining of iNOS was seen in schistosoma ova, ova granuloma, fibroconnective tissue and suppuratie cells. Conclusion The NO may play an important role in the pathogenesis of rectum ova granuloma.