目的 本文旨在探讨PM2.5致雄性大鼠生殖功能障碍的可能机制。方法 将30只雄性SD大 鼠随机分为 3 组：生理盐水对照组、PM2.5 低浓度（PM 4.3 mg/mL）暴露组和 PM2.5 高浓度（PM 12.9 mg/mL） 暴露组，每组 10 只。每隔 2 天经气管滴注法 PM2.5 混悬液（剂量：1 mL/kg），连续暴露 4 周后观察大鼠生长 状态并取材，计算睾丸系数并观察睾丸组织细胞形态学变化，检测血清睾酮含量、NF⁃κB 炎症信号通路 相关蛋白表达情况。结果 与对照组相比，实验组睾丸重量及睾丸系数减低。光镜下观察，实验组大鼠 睾丸组织曲细精管管壁变薄，各级生精细胞排列松散紊乱，管腔中成熟精子数量减少。与对照组相比， 实验组血清睾酮水平显著下降（P < 0.05）。Q⁃PCR 法结果表明，实验组炎性因子 IL⁃6、TNF⁃αmRNA 表达 量较对照组升高，差异有统计学意义（P < 0.05）；Western blot 法结果显示与对照组相比，NF⁃κB 信号通路 相关蛋白 IKK（IκB 激酶）、NF⁃κB、p⁃NF⁃κB p65、p⁃IκB⁃α 表达显著上调，差异有统计学意义（P < 0.05）。 结论 PM2.5 可能通过诱导 NF⁃κB 炎症信号通路，上调 IL⁃6、TNF⁃α 的表达，从而导致雄性大鼠生殖功 能障碍。

Objective To investigate the possible mechanism of PM2.5⁃induced reproductive dysfunction in rats. Method Thirtymale SD rats were randomly divided into normal saline control group，low concentration of PM2.5（PM 4.3 mg/mL）exposure group and high concentration of PM2.5（PM 12.9 mg/mL）exposure group，with 10 rats in each group. The suspension of PM2.5（dose：1 mL/kg）was given by intratracheal drip every 2 days. After successive 4 weeks，the growth of the rats was observed；the testis coefficient was calculated；the morphological changes of testicular tissue and cells were observed，and the serum testosterone content and the expression of protein related NF⁃κB inflammatory signal path were detected. Results Compared with those in the control group，testis weight and testis coefficient decreased in the experimental group. Light microscope found that in the experimental group，the wall of seminiferous tubule of testicular tissue in rats was thinner；spermatogenic cells at all levels were arranged loosely and disordered，and the number of mature sperm in the lumen decreased. Compared with that in the control group，the testosterone level in the experimental group was significantly decreased（P < 0.05）. Q⁃PCR results showed that the expression quantity of inflammatory factorIL ⁃ 6，and TNF ⁃ α mRNA in the experimental group were higher than those in the control group，and the differences were statistically significant（P < 0.05）. Western blotting showed that the expressions of protein IKK（IκB kinase），NF⁃κB，p⁃NF ⁃κB P65 and p⁃I κB⁃α related NF⁃κB signal path increased significantly when compared with the control group，and the differences were statistically significant（P < 0.05）. Conclusion PM2.5 may up ⁃ regulate the expression of IL ⁃ 6 and TNF ⁃ α through inducing NF⁃κB inflammatory signal path，then cause reproductive dysfunction in male rats.