Hauser K F, Toran-Allerand C D
Center for Reproductive Sciences, Columbia University, College of Physicians and Surgeons, New York, NY 10032.
Brain Res. 1989 Apr 17;485(1):157-64. doi: 10.1016/0006-8993(89)90677-x.
Androgen effects were studied in organotypic cultures of the E12 fetal mouse lumbosacral spinal cord labeled in utero with [3H]thymidine on E10. Following continuous exposure to androgens for one month in vitro, the number of labeled cells was significantly increased in whole explants, and in hemisected segments in the presence or absence of co-cultured fetal thigh muscle. Because lumbosacral motoneurons undergo their final mitosis predominantly on E10 and thus remain permanently labeled, the results suggest that androgens increase neuronal numbers by directly modulating motoneuron survival rather than stimulating mitosis. These findings demonstrate for the first time that in addition to the well documented role of the muscle target in motoneuron survival, the direct neuronotrophic effects of androgen at the level of the spinal cord must also be considered.
利用[3H]胸腺嘧啶核苷在子宫内对E10期的E12胎鼠腰骶脊髓进行标记，研究雄激素对其器官型培养物的作用。在体外连续暴露于雄激素一个月后，在整个外植体以及在存在或不存在共培养的胎儿大腿肌肉的半切节段中，标记细胞的数量显著增加。由于腰骶运动神经元主要在E10期进行最后一次有丝分裂并因此保持永久标记，结果表明雄激素通过直接调节运动神经元存活而非刺激有丝分裂来增加神经元数量。这些发现首次证明，除了肌肉靶标在运动神经元存活中已得到充分证明的作用外，还必须考虑雄激素在脊髓水平的直接神经营养作用。
