过表达肝/骨/肾型碱性磷酸酶对小鼠急性心肌梗死后心室重塑的影响

目的 探讨肝/骨/肾型碱性磷酸酶(ALPL)过表达对小鼠急性心肌梗死（MI）后心室重塑的影响。方法 36只8周龄雄性C57BL/6 J小鼠随机分为对照组(sham组)，心肌梗死组（MI+Adv-EGFP组）和ALPL过表达组（MI+Adv-ALPL组）,每组12只。术后2周，使用心脏彩色超声测定小鼠心脏功能，HE染色观察小鼠心脏组织病理变化，Real-time PCR检测小鼠心脏ALPL mRNA表达水平, Western blotting检测ALPL、α平滑肌肌动蛋白（α-SMA）、Ⅰ型胶原蛋白（ColⅠ）和Ⅲ型胶原蛋白（ColⅢ）表达情况，苦味酸天狼猩红染色偏振光法测定各组标本胶原容积分数(CVF)和Ⅰ型/Ⅲ型胶原比值。结果 与MI组相比，过表达ALPL组小鼠心脏左室射血分数(LVEF)及左室短轴缩短率(LVFS)明显下降（P<0.05)，过表达ALPL组HE染色可见心肌纤维断裂，排列紊乱，梗死区域纤维化明显，心脏组织α-SMA、ColⅠ、ColⅢ蛋白表达及CVF均显著增大（P<0.05），同时ColⅠ/ColⅢ比值显著增加（P<0.05）。结论 ALPL过表达加重小鼠急性心肌梗死后心室病理性重塑。

Effect of alkaline phosphatase liver/bone/kidney overexpression on ventricular remodeling after acute myocardial infarction in mice#br#

Objective To investigate the effect of alkaline phosphatase liver/bone/kidney (ALPL) overexpression on ventricular remodeling after acute myocardial infarction (MI).Methods Thirty six 8-week-old male C57BL/6 J mice were randomly divided into sham group（sham）, MI group (MI+Adv-EGFP) and ALPL overexpression group (MI+Adv-ALPL) with 12 mice in each group. Two weeks after MI，cardiac function of mice was detected by echocardiography, pathological changes was detected by HE staining. ALPL mRNA expression in mouse heart was detected by Real time PCR. The levels of ALPL, α-smooth muscle actin (α-SMA)，collagen Ⅰ (ColⅠ) and collagen Ⅲ (ColⅢ) protein were detected by Western blotting. The collagen volume fraction (CVF) and the ratio of ColⅠ/ColⅢ were measured by polarizing method with Sirius red staining. Results Compared with MI+Adv-EGFP group, the left ventricular ejection fraction (LVEF) (%) and left ventricular fractional shortening (LVFS) (%) of the heart in MI+Adv-ALPL group were reduced significantly (P<0.05). Hearts in the ALPL overexpression group showed myocardial fiber broken, and disordered and fibrous scars were obvious in myocardial infarction area. The expression of ALPL and the expression of α-SMA, ColⅠ and ColⅢ protein in MI+Adv-ALPL group increased significantly (P<0.05), and the proportion of ColⅠ/ColⅢ in MI+Adv-ALPL group increased significantly (P<0.05).Compared with MI+Adv-EGFP group, the CVF and the proportion of the ratio of ColⅠ/ColⅢ in the MI+Adv-ALPL group increased significantly (P<0.05).Conclusion ALPL overexpression can promote the ventricular pathological remodeling after acute myocardial infarction in mice.