Cytochemical and molecular biological analysis on the mechanisms of production and action of neurosteroids in the mouse cerebellum.

本研究旨在阐明神经小行星在小鼠小脑中的合成和作用机制，了解神经小行星在该脏器中的生理作用。结果如下：1)PCR法检测甾体合成酶（SCC、3β - hsd、17β - hsd、P450c17、芳香化酶、5α -还原酶）mRNA水平，Western blotting法检测蛋白水平。免疫细胞化学结果显示伯格曼胶质细胞中存在5α -还原酶，浦肯野细胞中存在5α -还原酶。2)用免疫细胞化学方法研究了5alfa-还原酶在新生小鼠小脑中的表达。在1周龄小鼠小脑中检测到该酶。外颗粒层在出生后1 - 3周形成。5alfa-还原酶的表达与这一层的形成很好地吻合。3)这些结果表明，类固醇合成酶的表达与小脑颗粒层的形成和颗粒层神经元的径向迁移密切相关。

This study aims to clarify the mechanism of synthesis and action of neurasteroids in tha mouse cerebellum, and to know the physiological roles of neurasteroids in this organ. Theresults obtained areas follows:1) Steroids synthesizing enzymes(SCC, 3beta-HSD, 17beta-HSD, P450c17, aromatase, 5alfa-reductase) were detected in mRNA level by PCR method and protein level by Western blotting. The results or immunocytochemistry indicated that 5alfa-reductase was present in the Bergmann glia and the other enzymes were in the Purkinje cells.2) The expression of 5alfa-reductase was immunocytochmically studied in the neonatal mice cerebellum. The enzyme was detected in the 1 week-old mice cerebellum. The outer granular layer is formed between 1 and 3 weeks after birth. The expression of 5alfa-reductase is well coincided with this formation of the layer.3) These results indicated that the expression of the steroid synthesizing enzyme are intimately associated with the formation of the granular layer in the cerebellum and radial migration of neurons in this layer.