HIF-1α在压力过负荷大鼠心肌组织中的表达

Expressive evolution of hypoxia-inducible factor-1α in pressure-overloaded rat hearts

目的探讨压力过负荷时大鼠心肌组织低氧诱导因子(HIF)-1α、血管内皮生长因子(VEGF)表达的变化。方法将45只雄性Wistar大鼠随机分为两组,即假手术组(15只)和模型组(30只)。采用腹主动脉缩窄法建立压力过负荷大鼠模型。分别在6周、12周后,制作两组大鼠的心肌组织切片,检测血流动力学指标以及心肌组织中HIF-1α及其靶基因VEGF的表达。结果与假手术相比,模型组大鼠心肌组织第6周出现明显肥厚(P<0.05);心肌组织HIF-1α及靶基因VEGF的表达明显增加,并于第12周出现心力衰竭(P<0.05);心肌组织中HIF-1α和VEGF的表达仍较假手术组增加(P<0.05),但较本组第6周大鼠表达明显减少(P<0.05)。结论压力过负荷造成的大鼠心肌肥厚组织,HIF-1α及靶基因VEGF的表达明显增加,但当出现心力衰竭时,HIF-1α和VEGF的表达则明显减少。

AIM To evaluate the expressive evolution of HIF-la and VEGF in pressure-overloaded rat hearts. METHODS Forty-five male Wistar rats were randomly divided into sham-operated group （n = 15） and model group （ n = 30）. Pressure-overloaded rat heart models were produced by abdominal aortic banding. After 6 weeks and 12 weeks, respectively, myocardium and hemodynamic performance were examined, and the expressions of HIF-1a and VEGF in myoeardium of rats were determined. RESULTS After 6 weeks, left ventricular hypertrophy increased in model group compared with sham-operated group （P 〈 0. 05）. The expressions of HIF-la and VEGF increased significantly in the model group （P 〈0.05）. After 12 weeks, the expressions of HIF-la and VEGF in the model group increased compared with those in the sham-operated group （ P 〈 0.05 ） , but the expressions decreased significantly compared with those during the 6th week in the same group. CONCLUSION When myocardial hypertrophy caused by pressure-overload exists, HIF-la and VEGF expressions increase significantly but decrease dramatically when heart failure occurs.