雄激素对雌激素引发去势雄性SD大鼠前列腺炎症及炎症因子的抑制作用

Inhibitory effect of testosterone on prostatitis and inflammatory factors of castrated male SD rats initiated by estrogen

目的给予不同比例苯甲酸雌二醇(E2)和丙酸睾酮(T)诱导SD大鼠前列腺炎,探讨炎症因子肿瘤坏死因子α(TNF-α)、环氧合酶2(COX-2)和巨噬细胞炎症蛋白1α(MIP^(-1)α)表达的变化。方法 SD大鼠无菌条件下去势后,颈背部分别sc给予E20.25 mg·kg^(-1)+T 0.25,0.5和1.0 mg·kg^(-1),连续给药30 d。取血离心取血清,采用ELISA检测E2,T和双氢睾酮(DHT)激素水平。HE染色观察前列腺组织病理变化,免疫组化检测前列腺中TNF-α,COX-2和MIP^(-1)α的表达。结果 ELISA检测结果显示,与假手术组比较,E20.25 mg·kg^(-1)组血清E2水平明显升高[(80±7)ng·L^(-1),P<0.01];E20.25 mg·kg^(-1)组和E2+T 0.25 mg·kg^(-1)组血清T水平显著下降[111±6和(111±5)nmol·L^(-1),P<0.05]。与去势对照组相比,E20.25 mg·kg^(-1)组血清E2明显升高[(80±7)ng·L^(-1),P<0.01],其他各指标未见统计学差异。光学显微镜观察发现,假手术组和去势对照组前列腺组织结构完整、腺腔和间充质无炎症细胞浸润;E20.25 mg·kg^(-1)组前列腺腺腔内有少量炎症细胞浸润,间充质未见炎症细胞浸润;E2+T 3个剂量组间充质内有少量炎症细胞浸润。假手术组前列腺上皮细胞及前列腺基质细胞胞浆内TNF-α,COX-2和MIP^(-1)α均为阴性表达或极少量表达,去势对照组和E20.25 mg·kg^(-1)组TNF-α,COX-2和MIP^(-1)α均为强阳性表达,E2+T 3个剂量组TNF-α,COX-2和MIP^(-1)α呈弱阳性表达。结论雄激素具有抑制雌激素引起的去势SD大鼠前列腺炎及炎症因子TNF-α,COX-2和MIP^(-1)α表达的作用。

OBJECTIVE To study the changes in inflammatory factors caused by prostatitis. METHODS SD rats were castrated under sterile conditions. E20.25 mg·kg-1＋ T 0.25, 0.5 and 1.0 mg·kg-1were given sc for 30 d, respectively. Serum samples were taken and levels of E2, T and dihydrotestosterone（DHT）were detected by ELISA. Pathological changes of prostate tissue were observed by HE staining. The expressions of tumor necrosis factor-alpha（TNF-α）, cyclooxygenase-2（COX-2） and macrophage inflammatory protein 1alpha（MIP-1α） in prostate were detected by immunohistochemistry. RESULTS ELISA detection showed that E2 levels were significantly increased[（80 ± 7） ng · L-1, P〈0.01]in E20.25 mg·kg-1group and that T levels were significantly decreased[111±6 vs（111±5） nmol·L-1, P〈0.05]in E20.25 mg·kg-1and E2＋T 0.25 mg·kg-1groups compared with the sham-operated group. E2 was significantly increased[（80±7） ng·L-1, P〈0.01]in E20.25 mg·kg-1groups compared with the castrated control. The sham and castrated control showed normal glandular epithelium without leukocyte infiltration.In E20.25 mg·kg-1group, extensive infiltration of inflammatory cells was found in the glandular lumens,suggesting the occurrence of chronic prostatitis. In each E2＋T groups, fewer inflammatory cells were noted in the stroma around glands. The expressions of TNF-α, COX-2 and MIP-1α in sham group were negative or low, while those of castrated control and E20.25 mg·kg-1groups were high, especial y in E20.25 mg·kg-1group. The expressions of TNF-α, COX-2 and MIP-1α in each E2＋ T group were significantly decreased.CONCLUSION Testosterone can inhibit prostatitis and the expression of inflammatory factors, such as TNF-α, COX-2 and MIP-1α, in castrated SD rats initiated by estrogen.