新生期注射谷氨酸单钠对大鼠其脑钙结合素表达的影响

为探讨谷氨酸单钠（monosodium glutamate,MSG）对脑钙结合素（calbindin-28kD,CB）表达的影响,选用新生SD大鼠29只,分为实验组和对照组,实验组设3g/kg和1g/kg2个剂量组,生后第3－9天经腹腔注射MSG,对照组设实验对照（注射生理盐水12mL/kg）和空白对照,满10周龄时4％甲醛灌注固定,取脑做冰冻冠状切片进行钙结合素的免疫组化反应。计算各组大鼠丘脑、下丘脑、海马及大脑基底核算脑区钙结合素阳性神经元数量。发现钙结合素能神经元分布数量具有脑区差异,且新生期注射谷氨酸单钠可使成年后某些核团的钙结合素阳性神经元增多,表明钙纱能神经元可抗谷氨酸神经毒性。

The Effects of Injection of MSG in Newborn Stage of the Calbindin-28 kD-expression in the Brain of the Rat

To investigate the effects of MSG on the calbindin-28kD-expression in the brain of the rat. Twenty-nine newborn SD rats were divided into two experimental groups and one control group.From the third to the ninth day after birth,the experimental rats were injected intraperitoneally with MSG 1 g/kg or 3 g/kg every day and the controls were given normal saline or untreated.After ten weeks,all the rats were perfused with and their brains were cut into sections and stained by using immunocytochemistry of calbindin-28kD(CB).CB-positive neurons in eight fields of the brain were enumerated under light microscopy.The results indicate that the distribution of CB-positive neurons in the brain of the rat is uneven and injection of MSG might increase the CB-expression in some fields of the brain,which suggest that calbindin-28kD positive neurons resist glutamic neurotoxicity.