缺锌对大鼠脑组织游离氨基酸和突触膜N-甲基-D-天冬氨酸受体含量的影响(英文)

THE EFFECTS OF ZINC DEFICIENCY ON THE CONCENTRATION OF BRAIN FREE AMINO ACIDS AND SYNAPTIC MEMBRANES N-METHYL-D-ASPARTATE RECEPTORS IN RATS

本研究进行了两系列实验以探讨缺锌对大鼠脑组织游离氨基酸和突触膜 N-甲基 -D-天冬氨酸受体含量的影响 .在第一系列实验中 ,把生长大鼠随机分为三组即缺锌组 (ZD)、对喂组 (PF)和缺锌补锌组 (ZS) ,分别饲喂低锌饲料 (3 .3 mg/kg)、常锌饲料但给料量与缺锌组一致以及先饲喂缺锌饲料 2 1 d后再饲喂常锌饲料 ,持续饲喂 3 5 d.饲养实验结束后 ,采取脑组织样本以分析其中的游离氨基酸的含量 .在第二系列实验中 ,第 1和第 2组的处理与实验 1一致 ,而第 3组则不限食地饲喂常锌饲料 ,持续饲喂 2 8d.然后取海马组织以分析其中的 NMDA受体的含量 .结果表明 ,缺锌显著降低端脑中游离谷氨酸、牛磺酸、苏氨酸、丝氨酸、丙氨酸、半胱氨酸和精氨酸含量 ,同时使海马中 NMDA受体的最大结合率降低 .

Two experiments were used to evaluate the effects of zinc deficiency on the concentration of free amino acids and N-methyl-D-aspartate (NMDA) receptor. In Exp.1, Growing rats respectively consumed a low zinc (3.3mg/kg) diet (ZD), the adequate zinc but restricted according to feed consumption of ZD group (PF) or an adequate zinc diet after a low zinc diet for 21d(ZS). The duration is 35d. The telencephalon tissues were used for free amino acid concentration analysis. In Exp. 2, The treatment of group 1 and 2 were similar to Exp.1, but the rats of group 3 consumed adequate zinc diet ad libitum. The duration is 28d. The hippocampus tissues were used for NMDA receptor concentration analysis. Zinc deficiency significantly reduced the concentration of glutamate, taurine, threonine, serine, alanine, cysteine and arginine in telencephalon tissues, and Bmax of NMDA receptors in hippocampus tissues. The results provides a good explanation for low learning and memory ability in zinc deficient rats.