生长激素对培养的下丘脑细胞发育及衰老的调控性影响

实验用不同浓度的生长激素（h-GH）作用于培养的下丘脑神经细胞，观察其对细胞发育和衰老的影响，发现h-GH能促进培养细胞存活、发育，增加突起长度和细胞平均面积，并促进网络的形成，较高浓度的h-GH（5～10mg／L）均导致发育期及成熟期中的培养细胞寿命明显缩短，较低浓度（1mg／L）h－GH对发育中的细胞寿命无明显作用，但能显著延长成熟期细胞的寿命。适量h-GH有延长细胞寿命的作用，而过量则促进细胞迅速出现衰老特征性变化；如大量脂褐素形成，神经元纤维增生及线粒体肿胀、变性，跑体中出现空泡，细胞器减少等细胞衰老常见的特征。这些病理性变化常为衰老神经元的特征性表现。因此h－GH等因子在细胞蛋白质代谢中的平衡失调，可能在细胞衰老发展过程中起一定作用。

THE MODULATION EFFECT OF GROWTH HORMONE ON THE DEVELOPMENT AND AGING PROCESS OF THE CURTURED NEURON OF HYPOTHALAMUS IN RATS

Using different doses of h-GH, we observed the effects on the developmental and aging process of curtured neuron of hypothalamus in rats.It was indicated that h-GH could improve the sur-viving and development of the neuron, increased the length of the neurite and mean diameter of the cell and benifited the formation of their networks. The higher doses of h-GH (5-10mg/L) shorted the life span of the neuron in the developmental and mature period significantly, and the lower dose (lmg/L)tured neuron but increased the life span of the ma-tured one. The suitable doses of h-GH increased the life span but the higher doses could induce some ag-ing characters of the neuron promptly such as lipo-fucin, neurofibrily, swelling and degeneration of the mitochondria, vacuole within the neuron, decrease of celluar organ, etc. These pathological changes are the characteristics of the aging of neuron, indi-cating that h-GH unbalance in the metabolism of protein in the cell might evoke some effect on the aging process of the neuron.