摘要
目的：了解雄激素对幼年大鼠雌雄异形性坐骨海绵体肌肌纤维形态的影响。材料和方法：给５天龄的雌性和雄性 Ｗｉｓｔａｒ大鼠持续５周肌肉注射丙酸睾丸酮（每天 ４０ ｍｇ／ｋｇ），用碱性（ｐＨ１０．４）预孵育液处理的肌球蛋白三磷酸腺苷酶染色法对坐骨海绵体肌肌纤维染色分型。结果：正常大鼠坐骨海绵体肌有两型肌纤维：直径较小、染成黑色的ⅡＡ型和直径较大、染成浅灰色的ⅡＢ型，其比例分别约为 ４０％和 ６０％。外源性雄激素使幼年雄性和雌性大鼠坐骨海绵体肌的ⅡＡ型肌纤维所占比例均减少约一半（Ｐ＜０． ０５），肌肉的横断面积均增加约一倍（Ｐ＜０． ０５），而肌纤维数没有明显增加。结论：大鼠坐骨海绵体肌两型肌纤维的正常比例与大鼠阴茎的正常勃起及其维持相关，雄激素可使大鼠生后发育的坐骨海绵体肌雄性化。
Objective: To understand androgen regulation of muscle fiber morphology in the sexually di- morphic Ischiocaversosus of rat. Meterials and Methods: Testosterone propionate injection(i. m. 40 mg/kg daily) was given to 5-day old Wistar rats for 5 weeks and the muscle fibers of the Ishio- cavernosus were classified according to the myosin-ATPase method with pH10. 4 preincubation. Results: The normal male rats had two fiber types: 40% of the muscle fibers were type ⅡA with smaller, darkly staining and 60% of the muscle fibers were type ⅡB with larger, lightly staining. Exogenous androgen reduced the proportion of type ⅡA to 50% of the control(P<0.05) and in- creased the sectional areas of the muscle by 100% (P<0. 05). There was no significant change in the number of muscle fibers. Conclusions: The two muscle fiber types and their proportions are helpful to the erection and its maintenance of the penis in the adult rats. Androgen can directly masculinize the Ischiocavernosus during the postmetamorphic development.
出处
《解剖学杂志》
CAS
CSCD
北大核心
1999年第5期404-407,共4页
Chinese Journal of Anatomy
基金
四川省教委资助课题
