感染日本血吸虫小鼠心脏损伤的观察

THE OBSERVATIONS OF CARDIAC PATHOLOGICAL CHANGES IN MICE INFECTED WITH SCHISTOSOMA JAPONICUM

为观察不同感染度日本血吸虫病小鼠急、慢性期心脏的病理、超微结构及相关生化代谢的变化 ,采用光镜、电镜对日本血吸虫病小鼠模型的心肌组织的病理变化进行观察 ,同时检测血清心肌酶 AST、CK活性 ,心肌组织超氧化物歧化酶 (SOD)活性及丙二醛 (MDA)含量。结果显示 ,自感染后第 8wk轻、重度感染组心肌组织均可见明显的病理改变。主要表现为心内膜、心肌及心肌血管急性炎性病变及慢性过程中的纤维母细胞增生 ,局部间质纤维化 ,线粒体肿胀 ,肌浆网扩张 ,糖原颗粒增多等变化。在心肌组织内发现有虫卵沉着 ,但未发现成虫。AST活性在第8、18wk,CK活性在第 13、18wk均显著升高。SOD活性先升高 (第 8wk)后降低 (第 13、18wk) ,MDA含量自第 8wk起持续升高。结果提示 ,日本血吸虫感染致宿主心脏损伤是虫卵沉着、氧自由基的继发损伤等因素共同作用的结果。

The changes of cardiac histopathology and myocardial ultra structure were observed under the light and electric microscope in mice infected with Schistosoma japonicum of various intensity in acute and chronic periods. The levels of serum enzyme CK and AST, SOD activities and MDA contents of myocardial were also measured. The results showed that the obvious pathological changes included inflammation of endocardium and myocardium and perivascunum in acute periods and proliferated of parts of fibroblast and stroma fibrosis in chronic periods. The changes of ultra structure of myocardium included swelling mitochondria, endoplasmic reticulum dilation and increasing of glycogen granules. There were eggs deposited in the heart tissues and adult schistosomes were not found. The activity of serum AST at the 8th week and the 18th week and the serum CK activities at the 13th, 18th week were significantly higher than control group. The activities of SOD in myocardium were higher at the 8th week and then decreased significantly at the 13th,18th week. The contents of MDA were significantly higher then control group since the 8th week. It suggested that the eggs deposition, the damage of oxygen free radical and other related factors may be taken an important role in those heart tissue damage after mice infected with S. japonicum .