年龄变化及人参皂甙Rg1对大鼠脑皮层细胞膜流动性的影响

EFFECTS OF AGE AND GINSENOSIDE RG1 ON MEMBRANE FLUIDITY OF CORTICAL CELLS IN RATS

用荧光偏振法，研究大鼠脑皮层细胞随年龄变化而引起膜流动性的改变及人参皂甙Ｒｇ１（Ｒｇ１）对老年鼠膜流动性的影响。实验表明，胎鼠与新生鼠（出生３ｄ）间、青年鼠（３月龄）与成年鼠（９月龄）间膜流动性无显著差异。青年鼠和成年鼠膜流动性明显低于新生鼠，老年鼠（２７月龄）膜流动性明显低于青年鼠和成年鼠。Ｒｇ１可显著增加老年鼠膜流动性。结果提示，膜流动性的变化可作为脑老化的一个指征；Ｒｇ１通过改善神经细胞膜流动性而发挥脑细胞保护作用。

Membrane fluidity was measured using fluorescence spectrophotometer in cortical cells isolated from Wistar rats of five age groups (fetal); neonatal (3 days), young (3 months), adult (9 months) and old (27 months). Neurons were enzymatically isolated and loaded with the fluorescent dye, DPH (1,6 diphenyl 1,3,5 hexatriene). The membrane fluidity of neonatal cells was shown to be significantly higher ( 1 485±0 211) than that in young cells ( 2 220±0 169), and that in young cells was significantly higher than that in old cells ( 2 842±0 143). No significant difference in fluidity, neither between fetal and neonatal cortical cells nor between young and adult ones was observed. Ginsenoside Rg1 (Rg1) is one of the important active principles of ginseng and shares many pharmacological effects of this plant. When treated with Rg1 (10, 20, 40 mg·kg -1 ), the membrane fluidity of old cortical cells significantly increased ( 2 670±0 108, 2 381±0 123, 2 000±0 101). These findings indicate a substantial alteration of membrane fluidity with neuronal aging. Increment of membrane fluidity provides an aspect in elucidating the mechanisms of Rg1′s antiaging action.