多氯联苯对大鼠肝脾乙氧基异吩恶唑脱乙基酶活性及膜脂流动性的影响

Alterations of EthoxyreSorufin O-deethylase Activity and Membrane Fluidity of Liver and Spleen in Rats Treated with Polychlorinated Biphenyls

多氯联苯(PCB)连续3天腹腔注射后,除可明显诱导雄性大鼠肝脏微粒体乙氧基异吩恶唑0-脱乙基酶(细胞色素P448)活性外在400mg/kg剂量水平下使脾脏S9组分中该酶活性增加3.3倍,说明尽管淋巴组织中混合功能氧化酶的活性极低,但仍可被化学致癌物诱导。在同样染毒条件下用DPH荧光探剂标记大鼠肝微粒体及脾脏S9组分膜脂质,均引起荧光偏振度和微粘度的显著升高,说明PCB对大鼠肝脏及脾脏生物膜有损伤作用,从而造成膜流动性下降。

Male Wistar rats were treated with polychlorinated biphenyls (PCB) via an intraperitoneal injection for 3 consecutive days. Ethoxyresorufin O-deethylase (EROD) activity and membrane fluidity of liver microsome and spleen S9 fraction were determined. The results showed that EROD activity of the liver microsome was induced 18 fold by PCB treatment while an induction of 3.3 was produced in rat spleen S9 fraction. The fluorescence polarization of DPH-labeled liver microsome and spleen S9 fraction and membrane microviscosity also were significantly incresed. These results showed that PCB induced cytochrome P448 activity and decreased the fluidity of membrane lipids in rat liver and lymphoid tissue.