常压慢性持续缺氧及低二氧化碳致幼鼠心室肥大及心肌细胞凋亡的观察

Ventricular hypertrophy and cardiocyte apoptosis induced by chronic normobaric hypoxia and hypocapnia in infant rats

目的:观察SD幼鼠在常压慢性持续缺氧及低CO2下心室肥大及心肌细胞凋亡的变化。方法:SD幼鼠于常压慢性持续缺氧低CO214 d及21 d后分别测量计算右心室/左心室加室间隔比值(RV/(LV+S))、右心室/100g体重(RV/100 gBW)及左心室加室间隔/100g体重比值((LV+S)/100 gBW)和右心室组织切片荧光染色、荧光显微镜观测凋亡率。结果:常压慢性持续缺氧低CO2下各组RV/(LV+S)和RV/100 gBW比值增加,与对照组比较差异具有统计学意义(P<0.01),并与缺氧时间成正比;各组间(LV+S)/100 gBW组间差异无统计学意义(P>0.05)。缺氧14 d组、缺氧21 d组的右心室组织心肌细胞凋亡率均比对照组明显上升(P<0.01),且以缺氧21 d组上升更为明显。结论:常压慢性持续缺氧低CO2可致SD鼠右心室肥大、右心室心肌细胞凋亡,其严重程度与暴露时间有关。

Objective： To observe the effect of chronic normobaric hypoxia and hypocapnia on the ventricular hypertrophy and cardiocyte apoptosis in infant SD rats. Methods： After receiving chronic normobaric hypoxia and hypocapnia for 14 days or 21 days, the ratios of right ventricle （RV）/left ventricle＋ventricular septum （LV＋VS）, RV/100g BW and （LV＋VS）/100 g BW were calculated, and the apoptosis of myocardial cells in RV was detected by Hoechst 33258 staining. Results： The ratios of RV/（LV＋S） and RV/100g BW, and cardiocyte apoptosis increased with the exposure time compared with control group（P〈0. 01）, but there was no significant difference in the ratio of （LV＋VS）/100g BW between 3groups（P〉0.05）. Conclusion：Chronic normobaric hypoxiaand hypocapnia can induce the RV hypertrophy and cardiocyte apoptosis in infant rats in a time-dependent manner.