褪黑素对离体培养的小鼠胸腺细胞凋亡及细胞周期进程的影响

目的:研究褪黑素对体外培养的小鼠胸腺细胞凋亡及细胞周期进程的影响. 方法:小鼠胸腺细胞体外培养前预先加入不同浓度褪黑素,培养4 h后,应用流式细胞术检测其凋亡小体百分率和细胞周期各时相细胞百分率的变化. 结果:小鼠胸腺细胞培养后其凋亡小体百分率明显升高,为培养前的6.9倍(P<0.001);G0/G1和S期细胞百分率与培养前相比未见明显变化,G2+M期细胞百分率呈增高趋势.预先加入2.0 mmol*L-1 褪黑素可使凋亡小体百分率明显降低(P<0.01),G2+M期细胞百分率明显增高(P<0.05). 结论:褪黑素可以减轻体外培养的小鼠胸腺细胞凋亡,并可诱导细胞发生G2阻滞.

Effect of melatonin on apoptosis and cell cycle progression of mouse thymocytes in vitro

Objective:In the present study the effects of melatonin (MLT) on apoptosis and cell cycle progression in mouse thymocytes in vitro was investigated.Methods:MLT of various concentrations was added into mouse thymocytes before culture in vitro. The percentages of apoptotic bodies and each phase cells in cell cycle 4 h after culture were measured with flow cytometry. Results: The percentage of apoptotic bodies in mouse thymocytes was increased significantly after culture and was reached 6.9 times in comparision with that before culture. The percentages of G 0/G 1 and S phase cells in thymocytes after culture had no change in comparision with that before culture, while The percentage of G 2+M phase cells tended to increase. As MLT (2.0 mmol·L -1 ) was added into mouse thymocytes before culture the percentage of apoptotic bodies in thymocytes was decreased significantly ( P <0.01) and the percentage of G 2+M phase cells increased significantly ( P <0.05). Conclusion:MLT could reduce the apoptosis in mouse thymocytes and induce the arrest of G 2 phase cells.