年龄及人参皂甙 Rg1 对大鼠大脑皮层 NO 释放的影响

探讨了NO与衰老的关系及与Rg1抗衰老机制的关系。用Griess法,³H-L-精氨酸转化法分别研究大鼠大脑皮层细胞NO含量及NOS活性,观察其随龄变化及人参皂甙Rg1(Rg1)对老年鼠NO及NOS的影响。实验表明,成年鼠(9月龄)与青年鼠(3月龄)NO含量及NOS活性无显著性差异。老年鼠(27月龄)脑皮层NO含量明显高于青年鼠和成年鼠,NOS活性也明显增高。老年鼠给予Rg1后可显著减少大脑皮层NO含量和降低NOS活性。结果提示,NO与衰老关系密切,Rg1的抗衰老作用与其对NOS活性的抑制有关。

EFFECT OF AGE AND GINSENOSIDE RG1 ON NITRIC OXIDE CONTENT AND NITRIC OXIDE SYNTHASE ACTIVITY OF CEREBRAL CORTEX IN RATS

Nitric oxide(NO) content and nitric oxide synthase(NOS) activity were measured in cerebral cortex isolated from Wistar rats of three age groups(young: 3 months; adult: 9 months; and old: 27 months). No significant differences in NO content and NOS activity between young and adult rats were found(P > 0.05). The NO content and NOS activity in old rats were shown to be significantly higher than those of young and adult rats(P < 0.01). When treated with Rg1(10, 20, 40 mg.kg-1), the NO content and NOS activity in old rats decreased. The inhibitory effect of Rg1 on NOS was found to be dose-dependent in the range of 10-40 mg.kg-1. The optimal reduction in NO content and NOS activity induced by Rg1 occurred at 40 mg.kg-1 for old rats(P < 0.01). In view of the close relationship of NO content and NOS activity with aging, the inhibitory effect of Rg1 on NOS activity, as shown by our results, might provide an explanation for its antiaging function.