脂多糖对裸鼹鼠肺脏组织影响的初探

A Preliminary Study on Effects of Lipopolysaccharide on Lung Tissues of Naked Mole Rats

目的观察和分析脂多糖(lipopolysaccharide,LPS)对裸鼹鼠肺脏组织形态结构和病理学相关指标的影响,初步探讨裸鼹鼠是否存在LPS耐受。方法雄性裸鼹鼠10只,随机分为实验组和对照组。实验组按体质量以10 mg/kg给药量腹腔注射LPS,对照组注射同等体积的0.9%NaCl溶液(生理盐水)。给药后6 h,采集肺脏,检测肺组织湿干重量比值;制作石蜡切片,经HE染色后,光学显微镜下观察肺组织显微结构;流式细胞仪检测肺组织细胞中活性氧含量、肺组织细胞凋亡率。结果实验组裸鼹鼠肺组织结构完整,肺泡孔内无明显渗出液和炎性细胞浸润等病变。与对照组比较,实验组肺组织湿干质量比未发生显著变化,早期凋亡率未发生显著变化,但晚期凋亡率显著升高(P <0.01),活性氧含量显著升高(P <0.05)。结论裸鼹鼠对LPS诱导的肺损伤有一定程度的耐受性,其具体机制有待进一步研究。

Objective To detect the effects of lipopolysaccharide(LPS) on lung morphology and pathological parameters, and explore the LPS tolerance in naked mole rats. Methods Ten male naked mole rats were randomly divided into an experimental group and a control group. The naked mole rats of the experimental group were injected with LPS at 10 mg/kg according the body weight, while the naked mole rats of the control group were injected with the same volume of normal saline. Six hours after the administration, lung tissues were collected to detect the ratio of wet to dry weight;paraffin sections were prepared and stained with HE, and the lung microstructure was observed under optical microscope;the level of reactive oxygen species(ROS) and the apoptosis ratio of lung tissue cells were detected by flow cytometry. Results Microscopic examination showed that the lung tissue structure of naked mole rats in the experimental group was intact, and there were no obvious exudate and inflammatory cell infiltration in the alveolar foramen. Compared with the control group, the ratio of wet to dry weight of lung tissues in the experimental group and the proportion of early apoptosis had no significant differences, but the proportion of late apoptosis and the content of ROS increased significantly(P < 0.01, and P < 0.05, respectively). Conclusion Naked mole rats can tolerate the lung injury induced by LPS to some degree, and the specific mechanism needs to be further studied.