大鼠海马神经元缺氧/复氧后caspase-3活性的变化

目的：研究caspase-3在体外培养的海马神经元缺氧／复氧损伤中的作用及其抑制剂的干预效果，为缺血性脑损伤的治疗提供实验资料。方法：诱导体外培养的大鼠海马神经元缺氧3h，再复氧12－4，并在缺氧前1h用不同剂量的caspase-3抑制剂Ac-DEVD-CMK进行干预处理，应用MTT比色法测定细胞存活率，底物裂解法caspase-3活性。结果：缺氧／复氧后大鼠海马神经元存活率逐渐降低，caspase-3活性明显增强，复氧24h达高峰；用Ac-DEVD-CMK预处理的海马神经元caspase-3活性降低，细胞存活率增高，并呈剂量依赖性。结论：体外培养的大鼠海马神经元缺氧及缺氧／复氧后出现迟发性死恨，caspase-3介导的细胞凋亡机制在这种损伤过程中起一定的作用，通过抑制其活性可产生神经保护作用。

Changes of caspase-3 activities in rat hippocampal neurons during hypoxia/reoxygenation

Objective: To study caspase-3 activities and the neuroprotective effect of caspase-3 inhibitor Ac-DEVD-CMK in primary cultures of rat hippocampal neurons during hypoxia/reoxygenation (H/R). Methods: After pretreated with Ac-DEVD-CMK or the vector DMSO fo 1 h, primary cultures of rat hippocampal neurons were induced to hypoxia for 3 h, followed by 12 to 48 h of reoxygenation. The neuronal viability was estimated by MTT assay, and caspase-3 cellular activities were measured by a colorimetric method using Ac-DEVD-pNA as a substrate. Results: During H/R, the cultured rat hippocampal neuronal viability gradually decreased, and caspase-3 activities in the primary cultures of rat hippocampal neurons were significantly increased, and peaked at 24 h of reoxygenation. Caspase-3 activities were decreased in the neurons pretreated with Ac-DEVD-CMK in a dose dependent manner. Conclusion: Delayed neuronal death is detected in cultured hippocampal neurons during H/R, and apoptosis mediated by caspase-3 may play an important role in it, and caspase-3 inhibitor has a neuroprotective effect on them.