超细纳米锌颗粒对心肌梗死小鼠心脏结构功能影响的研究

Effects of ultrafine nano zinc particles on cardiac structure and function in mice with myocardial infarction

目的探讨超细纳米锌颗粒对心肌梗死小鼠心脏结构及功能的影响。方法将36只ICR小鼠随机分为正常对照组、心梗组以及吸入组,每组12只。吸入组在心肌梗死造模成功2周后,将其放置在含500μg/m^3的雾化箱子中进行颗粒吸入,8周后,使用vevo2100检测小鼠心功能,并处死小鼠,取心脏组织。利用免疫荧光法检测心肌细胞大小变化,使用TUNEL检测心肌细胞凋亡,使用马松三色法检测心脏的胶原含量变化。结果吸入组、心梗组与正常对照组相比,EF值均有明显下降(P<0.05),且吸入组下降的更加明显。免疫荧光结果吸入组梗死区心肌细胞明显增大(P<0.05),且细胞凋亡数明显增加(P<0.05),同时马松三色法显示吸入心肌细胞胶原含量明显增加(P<0.05)。结论吸入超细纳米锌颗粒加剧心肌梗死后心脏的心室重构与功能变化,增加心肌细胞凋亡。

Objective To investigate the effects of ultrafine-nano zinc particles on cardiac structure and function in mice with myocardial infarction(MI). Methods 36 ICR mice were randomly divided into control group, MI group and the inhalation group, 12 mices in each group. After two weeks of successful MI, the inhalation group was placed in an atomized box containing 500 μg/m^3 for particle inhalation. 8 weeks later, the heart function of mice was measured with vevo2100, then all mice were sacrificed. Heart tissue were collected. Cardiomyocyte size were assessed by immunofluorescence. TUNEL method was used to detect the apoptosis of cardiac cells. The changes of collagen content in the heart were detected with Marsson trichrome staining. Results Compared with control group, the EF values in the inhalation group and MI group were significantly decreased(P<0.05), and the decrease in the inhalation group was more obvious. The results of immunofluorescence showed that cardiomyocyte size and the number of apoptotic cells in the inhalation group increased significantly(P<0.05). In addition Marsson trichrome staining results showed that the collagen content of cardiomyocyte in the inhalation group increasedsignificantly( P < 0. 05). Conclusion Inhalation of nano-zinc powder particles can aggravate ventricular remodeling and functional changes and exacerbate myocardial cell apoptosis of myocardial infarction.