Stengaard-Pedersen K
Acta Pharmacol Toxicol (Copenh). 1982 Mar;50(3):213-20. doi: 10.1111/j.1600-0773.1982.tb00964.x.
Zinc ions can totally block stereospecific binding of 3H-met-enkephalinamide (2-D-ala-5-L-methionine) to opiate receptor sites in synaptic membranes of the hippocampus, the cerebral cortex and the basal ganglia of the rat brain. Analysis of binding isotherms indicates that this inhibitory effect involves a decrease in both receptor affinity and the number of binding sites. Our data also suggest that the zinc ions react with essential SH-groups of the opiate receptor. The endogenous concentrations of zinc ions in the hippocampus, the cerebral cortex and the basal ganglia are compatible with the concentrations needed to inhibit opiate receptor binding in vitro. Especially the hippocampus contains a high concentration of zinc ion, which are localized exclusively in the giant boutons of the mossy fibers. Further, the hippocampal distribution of enkephalin and zinc ions is identical and confined to the mossy fiber zone. Hence, zinc ions may represent important modulators of opiate receptor binding in the central nervous system, particularly in the hippocampal mossy fiber zone.
锌离子能够完全阻断3H-甲硫氨酸脑啡肽酰胺（2-D-丙氨酸-5-L-甲硫氨酸）与大鼠脑海马、大脑皮层及基底神经节突触膜上阿片受体位点的立体特异性结合。结合等温线分析表明，这种抑制作用涉及受体亲和力和结合位点数量的降低。我们的数据还表明，锌离子与阿片受体的必需巯基发生反应。海马、大脑皮层及基底神经节中锌离子的内源性浓度与体外抑制阿片受体结合所需的浓度相符。尤其是海马中含有高浓度的锌离子，这些锌离子仅定位于苔藓纤维的巨大终扣中。此外，脑啡肽和锌离子在海马中的分布是相同的，且局限于苔藓纤维区。因此，锌离子可能是中枢神经系统中阿片受体结合的重要调节剂，尤其是在海马苔藓纤维区。
