铅对大鼠海马突触小体摄取谷氨酸递质的增强作用

Activation of Glutamate Uptake in Rat Hippocampal Synaptosome by Lead

为了探讨铅影响学习记忆功能的作用机制，作者进行了海马突触小体递质摄取实验。结果显示：３．１～５０．０μｍｏｌ／Ｌ剂量铅在体外作用１５分钟，能使突触小体３Ｈ－ＤＬ－谷氨酸摄取率增加７０．３８％～１９３．２４％，且存在明显的剂量效应关系。动物先经１０～１６００μｇ／ｍｌ剂量铅饮水染毒３０天，然后直接进行摄取实验，摄取率增加６５．７３％～１２４．９３％，与海马组织中铅含量存在剂量效应关系。提示铅离子能直接加速谷氨酸递质的灭活，产生抑制性作用。

In order to investigate the mechanism of effects of lead on learning and memory,an experiment of glutamate uptake in the hippocampal synaptosome of rats was carried out Results showed that (1) uptake of 3 H DL glutamate increased by 70 38% to 193 24% in the synaptosome by exposure to 3 1to 50 0μmol/L of lead for 15 minutes in vitro,with a dose dependent relationship;and (2) uptake of 3 H DL glutamate increased by 65 73% to 124 93% after exposuring to 10 to 1 600 μg/ml of lead in drinking water for 30 days, also in a dose dependent manner with lead content in the hippocampus It suggests that lead ion can accelerate the clearance of glutamate transmitter and cause inhibitive effects