Charrasse S, Jehan F, Confort C, Brachet P, Clos J
URA 1197 du CNRS, Université Montpellier II, France.
Dev Neurosci. 1992;14(4):282-9. doi: 10.1159/000111673.
Primary cultures of cerebellum from 5-day-old rats indicated that proliferating neuroblasts synthesize and release nerve growth factor (NGF). Since NGF promotes DNA synthesis in these cells, our findings demonstrate that the early developing cerebellum is a suitable physiological model for studying the autocrine mitogenic action of NGF. Thyroid deficiency led to a greater reduction in the NGF content of the cerebellum than of the olfactory bulbs or hippocampus. Cerebellar NGF mRNA was also very sensitive to hormone deprivation. Physiological amounts of thyroid hormone stimulated both the mitotic activity and NGF production of cultured cerebellar neuroblasts. A lack of thyroid hormone is known to markedly alter cell formation in the cerebellum where postnatal neurogenesis is highly significant, in contrast to the olfactory bulbs and hippocampus. Taken together, these results suggest that the hormonal control of cell formation in the cerebellum is, at least partly, mediated by the autocrine mitogenic action of NGF. The thyroid hormone could temporally regulate the transient NGF synthesis by cerebellar neuroblasts directly and/or through its ontogenetic action, and hence all the NGF-dependent trophic effects.
对5日龄大鼠小脑进行原代培养表明，增殖的成神经细胞可合成并释放神经生长因子（NGF）。由于NGF可促进这些细胞中的DNA合成，我们的研究结果表明，早期发育的小脑是研究NGF自分泌促有丝分裂作用的合适生理模型。甲状腺功能减退导致小脑NGF含量的降低幅度大于嗅球或海马体。小脑NGF mRNA对激素缺乏也非常敏感。生理量的甲状腺激素可刺激培养的小脑成神经细胞的有丝分裂活性和NGF产生。已知甲状腺激素缺乏会显著改变小脑的细胞形成，与嗅球和海马体不同，小脑的产后神经发生非常显著。综上所述，这些结果表明，小脑细胞形成的激素控制至少部分是由NGF的自分泌促有丝分裂作用介导的。甲状腺激素可直接和/或通过其个体发育作用在时间上调节小脑成神经细胞短暂的NGF合成，从而调节所有依赖NGF的营养作用。
