摘要
目的研究腹主动脉部分缩窄大鼠模型心肌肥厚动态变化特点。方法雄性SD大鼠35只分为正常组5只,假手术10只,模型组20只,后两组的半数分为4周组和18周组。造模方法:在大鼠肾动脉上方约1 cm的腹主动脉处,将直径0.7 mm的注射针头与腹主动脉一起结扎,然后抽出针头。术后4周、8周采用飞利浦HDI5000超声诊断仪、15 MHz高频线阵探头,经胸骨旁左室长轴切面及腹主动脉的长轴切面进行检测。结果造模后第4周模型组与假手术组比较:室间隔舒张末期厚度(IVSTd)明显增加(P<0.01),左室舒张末期内径(LVDd)和左房收缩末内径(LADs)无明显变化,左室心肌质量指数(LVMI)明显增加(P<0.01),左室射血分数(EF)无明显变化;造模后第8周模型组与假手术组比较:IVSTd继续非常显著增加(P<0.01),LVPWTd非常显著增加(P<0.01),LVDd显著增加(P<0.05);左房收缩末内径(LADs)明显增大(P<0.01);LVMI非常显著性增大(P<0.01),左室射血分数(EF)明显减小(P<0.05)。造模后第4周及第8周,模型组缩窄处血流压差均非常显著地大于近心端(P<0.001);腹主动脉缩窄率(%)分别为77.74±4.43%和79.23±3.97%。结论超声心动仪在动态研究大鼠心脏心室重构中具有重要应用价值;部分缩窄大鼠腹主动脉模型的早期是由压力负荷致心脏左室向心性肥厚的模型,随着压力负荷的持续和容量负荷的增加,左室逐渐演变为向心性肥厚和离心性肥厚的混合型肥厚。
Objective To study the dynamic state characteristics of heart in rat with partial coarctation in the abdominal aorta. Methods Thirty-five male rats were randomly divided into normal （n = 5）, operation （n = 20） and sham-operation （n = 10） groups. Operation methods： A needle （diameter 0.7 mm） was inserted and ligated in the abdominal aorta, and then the stylet was drawn out. Parasternal long axis and abdominal aorta long axis images were acquired by a 15 MHz high-frequency linear ultrasound transducer at 4 weeks and 8 weeks after operation, respectively. Results Compared with sham-operation groups, after 4 weeks, the operated rats showed increased interventricular septum thickness （P 〈 0.01 ） and left ventricular mass （P 〈 0.05）.However, the left ventricle diameter, left atria diameter and ejection fraction had no significant difference. While after 8 weeks, the operated rats had increased interventricular septum thickness （ P 〈 0.01 ）, posterior left ventricular wall thickness （ P 〈 0.01 ） and left ventricular mass （ P 〈 0.01 ）. Moreover, left ventricle diameter （ P 〈 0.05 ） and left atria diameter （ P 〈 0.01 ） in the operation group were increased markedly, whereas ejection fraction （P 〈 0.05） was decreased markedly. After both 4 weeks and 8 weeks, in the operation group, the blood flow gradient pressure in coaretation was larger than in the proximal part （ P 〈 0.001 ）, the rates of abdominal aorta were 77.74 ± 4.43 % and 79.23 ± 3.97 %, respectively. Conclusion High-frequency ultrasound has a high application value in rat heart studies. The left ventricle of rat with partial coaretatic abdominal aorta is concentric hypertrophic, induced by pressure overload in the early stage. With the pressure load continuing and volume load increasing, the left ventricle is evolving gradually into mixed type hypertrophy including both concentric and eccentric hypertrophy.
出处
《中国比较医学杂志》
CAS
2007年第4期214-218,共5页
Chinese Journal of Comparative Medicine
基金
北京市教育委员会共建项目计划课题(编号:JD100260537)
关键词
腹主动脉部分缩窄
心肌肥厚
大鼠
超声心动图
Partial coaretation, abdominal aorta
Myocardial hypertrophy
Rat
High-frequency ultrasonography
