急性镉中毒大鼠睾丸氧化损伤机制的研究

目的:探究急性镉中毒睾丸氧化损伤的特点以及睾丸对镉敏感的可能机制.方法:通过观察MDA、还原态GSH、SOD、CAT、GSHpx、MT等指标系统研究大鼠肝、睾丸两器官的细胞抗氧化体系在急性镉暴露后的时间变化规律.结果:急性镉中毒使肝、睾丸两器官均发生严重的氧化损伤,细胞的抗氧化能力明显降低.但两者的变化规律不同:肝脏在6 h组MT大量表达(达正常值的6.7倍)后,上述损伤逐渐减轻;而睾丸MT表达的氧化损伤尽管在前3 h并不严重,但此后不断加剧.结论:急性镉中毒时睾丸与肝氧化损伤规律明显不同,MT在睾丸中不能被诱导表达是睾丸对镉极其敏感的原因之一.

Oxidative injury mechanism of acute cadmium-exposed rat testis

Objective: To study the role of metallothionein in cellular antioxidant system and the reason of testis highly sensitive to cadmium(Cd). Methods: Changes of cellular antioxidant system in acute Cd 2+ exposed rat testis and liver were observed. Indexes included oxidant damage index (MDA and deoxidized GSH), activities of cellular antioxidant enzymes (SOD, CAT and GSHpx) and MT expression level. Results: A single dose Cd 2+ exposure would cause lipid peroxidation, excessive ROS production and loss of intracellular redox potential in both testis and liver. Their patterns of changes were different: the former oxidant damage quickly lightened since MT was induced in 6 h group in liver, although it was not so serious in first 3 h in testis, the oxidant injury was not controlled by 48 h. MT could be induced in testis until 48 h after acute Cd 2+ exposure. Conclusion: Metallothionein plays a major role in the cellular antioxidant defense system, it is a highly effective eliminator of Cd. MT can't be induced in testis is the important reason that testis is highly sensitive to Cd.