超声介导重组腺相关病毒载体心肌靶向转染对大鼠左室心功能的影响

目的 探讨超声造影剂介导下重组腺相关病毒载体(rAAV2-GFP)心肌靶向转染前后大鼠左室心肌功能的变化.方法 健康成年SD大鼠20只,随机分为对照组与实验组:对照组尾静脉注射超声造影剂+超声照射;实验组注射携带rAAV2-GFP造影剂+超声照射.分别于实验前和实验后14 d利用斑点追踪技术测量大鼠周向应变、收缩期应变率,舒张期应变率、扭转角度,并同时测量大鼠射血分数、短轴缩短率、舒张末期容积及收缩末期容积等左心功能指标.行心肌组织冰冻切片,荧光显微镜下观察GFP的表达情况.结果 超声介导重组腺相关病毒心肌靶向转染前后大鼠左室心肌功能指标及相对于心底水平的扭转角度及达峰时间的差异均无统计学意义(P>0.05).结论 超声及超声造影剂介导重组腺相关病毒载体靶向转染心肌组织对大鼠左室心肌功能无影响.

The changes of left ventricular myocardial function before and after rAAV2 targeted to myocardium by ultrasound mediated microbubbles

Objective To study the changes of left ventricular(LV) function before and after rAAV2-GFP targeted to myocardium by the ultrasound mediated microbubbles. Methods Twenty rats were divided into 2 groups. Ten rats underwent ultrasound mediated microbubbles destruction without rAAV2-GFP as control. Another ten rats underwent ultrasound mediated microbubbles destruction containing rAAV2-GFP as experimental group. The mean value of LV rotation of rats was obtained in apical and base plane using speckle tracking imaging(STI) software. LV torsion(LVtor) was defined as apical rotation relative to the base. LV function including circumferential strain,circumferential strain rate of systolic and early diastolic and late diastolic, torsion, time to peak, ejection fraction, fractional shortening, end-diastolic volume, end-systolic volume of LV,heart rate and so on were also measured before and after 14 days. Other rats were killed after 14 days and hearts were harvested. GFP protein expression which showed rAAV2 transfer was observed under fluorescence microscope in frozen section. Results There was no significant difference of LV function of rats before and after rAAV2-GFP myocardium transfection by the ultrasound mediated microhubbles. Conclusions LV myocardial function has no significant difference before and after delivering rAAV2 to the heart in vivo by ultrasound-mediated microbubbles destruction.