Gerbil 해마에서 일시적 대뇌허혈에 의한 신경세포의 Apotosis에 미치는 Zinc의 효과에 관한 면역조직학 및 전자현미경적 연구

Zinc is one of the trace elements playing an important role in many fundamental biological process. The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca²+, Mg²+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal cell death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty adult Mongolian gerbils of male underwent transient bilateral clipping the common carotid arteries for 5 min. In the pretreated animals, ZnCl₂(20mg/kg) was injected subcutaneously once, 1hr before ischemia. Histological survey was carried out 4 days later by in situ DNA fragmentation method and hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. And ultrastructural study was also undertaken to determine the effect of zinc on the evolution of transient global ischemia-induced neuronal injury in the gerbil hippocampus. In histological and ultrastructural study, pretreatment of zinc significantly reduced the nuclear damage and subsequent neuronal death against ischemic damage. The result of the present study suggest that the pretreatment of zinc might be an effective tool for the treatment of cerebral ischemia.