低能激光对大鼠梗死心肌中血管内皮生长因子和诱导型一氧化氮合酶的影响

Effect of low level laser irradiation on vascular endothelial growth factor and inducible nitric oxide synthase contents in myocardial infarction tissues of rats

目的观察低能激光照射（LLu）对大鼠梗死后心肌组织中血管内皮生长因子（VEGF）和诱导型一氧化氮合酶（iNOS）表达的影响及意义。方法将110只SD大鼠随机分为假手术组、对照组和治疗组。对照组和治疗组通过结扎左冠状动脉前降支制作心梗模型，假手术组同部位只穿线不结扎，3周后治疗组使用LLu处理梗死区域，对照组和假手术组照射同一区域但治疗仪不接通电源，各组分别于照射后1、24、48、72h、1周使用Westernblot法检测梗死心肌中VEGF和iNOS的表达。结果在LLLI处理后，治疗组VEGF的表达在1～48h持续上升，峰值表达与对照组比较（2．27±0．22比1．46±0．19，P〈0．05）差异有统计学意义，治疗组iNOS表达在照射后1h开始升高，48h达到峰值，与对照组比较（1．90±0．18比1．40±0．08，P〈0．05）差异有统计学意义；第2次开胸后1周对照组与治疗组比较：左室射血分数（LVEF）显示[（39．83±1．64）％比（47．62±2．75）％，P〈0．05]，左室短轴缩短率（LVFS）显示[（18．03±1．25）％比（24，15±2．53）％，P〈0．05]，差异有统计学意义；LLu后1周新生毛细血管密度对照组与治疗组比较[（69．50±14．50）／mm^2比（111．50±9．00）／mm^2，P〈0．05]，差异有统计学意义。结论LLLI处理能明显上调梗死后心肌组织中VEGF和iNOS的表达，促进血管再生，改善梗死区微循环，提高心功能。

Objective To observe the low level laser irradiation （LLLI） rats with myocardial in- farction after vascular endothelial growth factor （YEGF） and inducible nitric oxide synthase （iNOS） ex- pression of the impact and significance. Methods 110 SD rats were divided into three groups： sham group, the control group and the treatment group. The control and treatment groups by ligation of the left anterior descending coronary artery produced myocardial infarction model, sham group wearing the same site without ligation, three weeks after the treatment group LLLI treatment infarct area, the control group and the sham group irradiating the same area but treatment device does not power on, each group 1, 24, 48, 72 h, 1 week use of VEGF and iNOS Western blotting assay infarcted myocardial tissue expression af- ter irradiation, respectively. Results After the 2nd thoracic irradiation treatment, the expression of VEGF treatment group continued to rise in 1 -48 h, peak expression compared with control group （2. 27 ± 0. 22 vs. 1.46 ±0. 19, P 〈0. 05） was statistically significant, the treatment group iNOS the expression began to increase after irradiation 1,48 h peak, compared with control group （ 1.90 ±. 18 vs. 1.40 ±0. 08, P 〈 0. 05） with statistical significance; after the second thoracotomy 1 week treatment group and the control group： left ventricular ejection fraction （LVEF） display [ （39. 83 ± 1.64）% vs. （47.62 ±. 75）% , P 〈 0. 05 ] , left ventricular fractional shortening （LVFS） display [ （ 18.03 ±1.25 ） % vs. （ 24. 15 ± 2. 53 ） % , P 〈 0. 05 ] , a statistically significant result; 1 Zhou Xinsheng after LLLI capillary density in the control group and the treatment group [ （69. 50 ± 14. 50）/mm^2 vs. （ 111.50 ±9. 00）/mm^2, P 〈0. 05], with sta-tistical significance. Conclusion LLLI treatment can significantly increase the expression of VEGF after myocardial infarction and iNOS, and promote angiogenesis and improve microcirculation infarction, improve cardiac function.