褐黑素对大鼠海马神经元谷氨酸所致毒性的拮抗作用

在大鼠海马脑片上电刺激Ｓｃｈａｆｆｅｒ侧支纤维,胞外记录ＣＡ１区锥体细胞层诱发群体锋电位,观察灌流谷氨酸和褪黑素对ＰＳ的影响。结果显示：５．０ｍｍｏｌ／Ｌ浓度的Ｇｌｕ可使ＰＳ值下降至对照值的４．１％;ＭＥ（０．４、０．５和０．６μｍｏｌ／Ｌ）一５．０ｍｍｏｌ／Ｌ浓度的Ｇｌｕ可使ＰＳ值下降至对照值的１４．７％、１０５．２％、２４．３％;ＭＥＬ、Ｇｌｕ,与赛庚啶混合给药,ＰＳ值下降至０。上述结果提示。

Antagonistic effects of melatonin on glutamate-induced neurotoxicity in rat hippocampal neurons

The effects of glutamate (Glu) and melatonin (MEL) on the evoked populaion spike (PS) following stimulation of the schaffer collateral fiber were studied by extracellular recording technique in perfused slices of rat hippocampus: 5.0 mmol/L Glu decreased the PS peak values to 4.1% of control. This effect of Glu (5.0 mmol/L) on PS peak values was changed to 14.7%, 105.2% and 24.3% of control by 0.4, 0.5, 0.6 mumol/L of MEL. But when the interaction between MEL (0.5 mumol/L) and Glu (5.0 mmol/L) was entirely suppressed by CDP (0.5 mumol/L), the PS values reduced to zero. These results suggest that the inhibitory action of MEL on Glu-induced neurotoxicity may be mediated by 5-HT receptors.