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移植神经干/祖细胞有助于受损脑组织形态和功能的恢复。移植部位的微环境及移植细胞与宿主细胞间的通讯在神经干/祖细胞移植的神经保护机制中有重要意义。笔者既往研究显示，对中枢轴索损伤动物进行神经干/祖细胞移植有助于恢复损伤神经元的电活动及突触联系，并可增加神经营养因子的释放。本研究拟观察移植的神经干/祖细胞与宿主胶质细胞间的解剖关系，以探讨神经干/祖细胞移植的神经保护作用的可能机制。从新生大鼠的脑室下区提取神经干/祖细胞移植到内侧纵束横断伤模型大鼠脑内。移植后8周取脑进行相关检测。免疫组化检测结果显示，与未移植神经干/祖细胞的大鼠相比，移植了神经干/祖细胞的大鼠脑内更多的小胶质细胞被激活。移植的神经干/祖细胞聚集在激活的小胶质细胞和星形胶质细胞附近。缝隙连接蛋白CX-43表达在损伤部位的神经干/祖细胞和胶质细胞上，且较多的存在于移植细胞和胶质细胞相连接的部位。移植的神经干/祖细胞和宿主胶质细胞及宿主小胶质细胞间均形成了缝隙连接，但移植的神经干/祖细胞和宿主胶质细胞间的缝隙连接较多。本研究结果显示，神经干/祖细胞移植对脑损伤导致的胶质细胞活化有调节作用，并可能通过在移植细胞和宿主细胞间建立缝隙连接来调节细胞间的通讯，这可能是细胞移植的神经保护作用的机制之一。“,”Transplantation of neural stem/progenitor cells (NPCs) in the lesioned brain is able to restore mor-phological and physiological alterations induced by different injuries. The local microenvironment created at the site of grafting and the communication between grafted and host cells are crucial in the beneficial effects attribut-ed to the NPC implants. We have previously described that NPC transplantation in an animal model of central axotomy restores firing properties and synaptic coverage of lesioned neurons and modulates their trophic factor content. In this study, we aim to explore anatomical relationships between implanted NPCs and host glia that might account for the implant-induced neuroprotective effects. Postnatal rat subventricular zone NPCs were iso-lated and grafted in adult rats after transection of the medial longitudinal fascicle. Brains were removed and ana-lyzed eight weeks later. Immunohistochemistry for different glial markers revealed that NPC-grafted animals dis-played significantly greater microglial activation than animals that received only vehicle injections. Implanted NPCs were located in close apposition to activated microglia and reactive astrocytes. The gap junction protein connexin43 was present in NPCs and glial cells at the lesion site and was often found interposed within adjacent implanted and glial cells. Gap junctions were identified between implanted NPCs and host astrocytes and less frequently between NPCs and microglia. Our results show that implanted NPCs modulate the glial reaction to le-sion and establish the possibility of communication through gap junctions between grafted and host glial cells which might be involved in the restorative effects of NPC implants.