摘要
目的观察博莱霉素(BLM)造模大鼠肺微血管内皮细胞(EC)紧密连接及Cx43表达的变化特征,探讨其在肺纤维化发生中的作用和意义。方法健康SD大鼠随机分为对照组和实验组每组20只,采用ELISA法测定对照组和实验组第3、7、14、28天血浆血管性假血友病因子(vWf)水平。对采血后的大鼠,分别在第3、7、14、28天行硝酸镧灌注,制作肺组织病理标本,用透射电镜观察血管EC紧密连接及镧颗粒分布;采用组织块培养法行肺微血管EC体外培养,用激光共聚焦显微镜观察Cx43表达。结果各实验组大鼠血清中vWf水平均高于对照组,以第3天最高,差异有统计学意义(P<0.01)。对照组EC结构完整,EC间连接紧密,未见镧盐颗粒通过EC间的紧密连接。实验组均可见EC连接间隙增宽,并有高密度的镧盐颗粒在细胞连接间隙中线状沉淀。实验组Cx43阳性反应的范围及强度均明显减弱,第3、7、14、28天Cx43蛋白的荧光反应强度及表达阳性率(25%、38%、45%、71%),均明显低于对照组,差异有统计学意义(P<0.05)。结论EC紧密连接呈持续开放状态,导致炎性细胞渗出及与之相应的细胞因子分泌持续增加,启动成纤维细胞增殖过度可能是BLM诱发肺间质结构发生异常改变的重要病理基础。
Objective To investigate the changes of expression of connexin-43 （Cx43） and the tight junction of microvessel endothelial cells （EC） to approach the effects in bleomycin （BLM） induced pulmonary fibrosis （PF）. Methods Forty healthy rats were equally and randomizedly divided into the control group and the experiment group.in beth group, vWf in blood serum was measured with ELISA method on 3rd,7th, 14th,28th day after BLM treatment.Rats in each group were infused with lanthanum nitrate on 3rd,7th, 14th,28th day after BLM treatment. The lung samples were made and the tight junction and the distribution of the granules of lanthanum in the microvessel EC were observed with transmission dectron microscopy in the control and experiment groups.The lung microvessel EC of the rats in each group were preserved by tissue culture methods at the same time, and the expression of Cx43 were observed by laser scanning confocal microscopy. Results The serum vWf in the peripheral blood of the experiment group was significantly higher than that of the control group, and was the highest on 3rd day after BLM treatment （ P 〈 0.01 ）. The blood vessel EC of the control group were intact. The basement membrane was uninterrupted. Granules of lanthanum nitrate did not penetrate the tight junction of EC. The width of junction gap in the experimental group was increased and the lanthanum granules of high density were found deposited in the linear form in the gap junction. Low expression of Cx43 was observed in experiment group. The expression rate of Cx43 was 25%,38% ,45% and 71% respectivly on 3rd,7th, 14th,28th day, significantly less than those in the control group （P〈0.05）. Conclusion It may be the important pathological basis for the BLM induced abnormality of the interstitial tissues in the lung that the tight junction of EC is continuously in the open state, which causes the effusions of inflammatory cells and the corresponding cytokine secretion, and thus initiates the overprolifelation of fibroblasts.
出处
《中华劳动卫生职业病杂志》
CAS
CSCD
北大核心
2006年第2期99-102,共4页
Chinese Journal of Industrial Hygiene and Occupational Diseases
