Szewczyk B, Kata R, Nowak G
Institute of Pharmacology, Polish Academy of Sciences, Kraków.
Pol J Pharmacol. 2001 Nov-Dec;53(6):641-5.
Zinc and magnesium are potent inhibitors of the NMDA receptor complex. Previous reports demonstrated that both zinc and magnesium, like other NMDA receptor antagonists, exhibit antidepressant-like effects in rodent screening tests. Moreover, chronic treatment with antidepressants and electroconvulsive shock increase zinc concentration in the rat hippocampus. The present study examined the effect of tricyclic antidepressant, imipramine, on the potency of zinc and magnesium to inhibit [3H]MK-801 binding in the mouse and rat cerebral cortex and hippocampus. Chronic treatment with imipramine produced statistically significant increase in the potency of zinc to inhibit [3H]MK-801 binding in the mouse cerebral cortex but not in the hippocampus. However, this treatment neither influenced the zinc affinity in rat tissue nor magnesium affinity in tissue of both species. The present data indicate that, although imipramine-induced rise in zinc affinity to the NMDA receptor complex is in agreement with previously reported antidepressant-induced reduction of the NMDA receptor function, this effect is species-specific.
锌和镁是N-甲基-D-天冬氨酸（NMDA）受体复合物的强效抑制剂。先前的报告表明，锌和镁与其他NMDA受体拮抗剂一样，在啮齿动物筛选试验中表现出类抗抑郁作用。此外，用抗抑郁药和电休克进行慢性治疗会增加大鼠海马体中的锌浓度。本研究考察了三环类抗抑郁药丙咪嗪对锌和镁抑制小鼠和大鼠大脑皮层及海马体中[3H]MK-801结合能力的影响。丙咪嗪慢性治疗使锌抑制小鼠大脑皮层中[3H]MK-801结合的能力出现统计学上的显著增加，但对海马体无此作用。然而，该治疗既不影响大鼠组织中的锌亲和力，也不影响两种物种组织中的镁亲和力。目前的数据表明，尽管丙咪嗪诱导的锌对NMDA受体复合物亲和力的升高与先前报道的抗抑郁药诱导的NMDA受体功能降低一致，但这种作用具有物种特异性。
