低能激光照射对大鼠梗死心肌抗氧化因子的影响

Effect of low level laser irradiation on anti - oxidant factors in infracted myocardial tissues of rats

目的观察不同能量密度低能激光照射（LLLI）对大鼠梗死区抗氧化因子超氧化物岐化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH—Px）的影响。方法开胸直视下结扎冠状动脉制作SD大鼠心肌梗死模型。3周后经胸心脏彩超筛选符合入组条件的大鼠，随机分为：对照组：仅开胸放置激光探头，不进行低能激光照射（n=20）；低能激光照射：二极管激光治疗仪，波长635nm，输出功率6mW，据不同能量密度分为：0．32J／cm2（A组，n=20）、0．64J／cm2（B组，n=20）、0．96J/cm2（C组，n=20）、1．28J／cm2（D组，／t=20）、1．60J/cm2（E组，n=20）。LLLI处理后48h采集梗死心肌标本，以比色法测定SOD、CAT、GSH．Px的活性。结果A、B、c、D、E组SOD、CAT、GSH．Px的活性[（0．57±0．13）、（0．29±0．05）、（0．26±0．03）U/mg；（0．65±0．08）、（0．31±0．02）、（0．30±0．06）U/mg；（0．95±0.09）、（0．39±0．04）、（0．41±0．04）U/mg；（0．94±0．07）、（0．38±0．03）、（0．40±0．03）U/mg；（0．93±0．10）、（0．38±0．01）、（0．39±0．04）U/mg]与对照组[（0．45±0．11）、（0．16±0．03）、（0．15±0．02）U/mg]比较明显升高（P均=0．000）。与A组比较，B组SOD、CAT、GSH-Px的活性明显升高（P=0．019、0．023、0．031）。与B组比较，C组SOD、CAT、GSH-Px的活性明显升高（P=0．001、0．017、0．006）。与C组比较，D组SOD、CAT、GSH-Px的活性差异无统计学意义（P=0．198、0．347、0．269）。与D组比较，E组SOD、CAT、GSH-Px的活性差异无统计学意义（P=0．634、0．512、0．491）。结论0．96J／cm2。的能量密度为LLLI治疗大鼠急性心肌梗死的最佳能量密度。

Objective To investigate the effect of low level laser irradiation （LLLI） with different energy density on anti -oxidant factors： superoxide dismutase （SOD） , catalase （CAT） and glutathione peroxidase （ GSH - Px） in infarcted myocardial tissues of rats. Methods The SD rat myocardial infarction model was established by ligating coronary artery under thoracotomy. Three weeks later, the rats undergoing transthoracie eehocardiography were randomly divided into six groups： the control group and groups A, B, C, D, E. The control group received coronary artery ligation but no laser irradiation was given （n = 20 ）. The rest five groups received LLLI （635 nm,6 mW diode laser） with the corresponding energy density （J/cm2 ） individually being 0. 32 （ group A, n = 20）, 0. 64 （ group B, n = 20 ）, 0.96 （ group C, n = 20 ）, 1.28 （ group D, n = 20） and 1.60 （ group E, n = 20）. The infarcted myocardia were excised at 48 h after LLLI. The activities of SOD, CAT and GSH - Px were measured by colorimetric method. Results The activities of SOD, CAT and GSH -Px in groups A, B, C, D, E [ （0. 57 ±0. 13）, （0. 29 ±0. 05）, （0.26±0.03） U/mg; （0.65± 0.08）, （0.31± 0.02）, （0.30± 0.06） U/mg; （0.95-± 0.09）, （0.39±0.04）, （0.41±0.04） U/mg; （0.94±0.07）, （0.38±0.03）, （0.40±0.03）U/mg; （0. 93 ± 0. 10）, （0. 38 ± 0. 01 ）, （ 0. 39 ± 0.04） U/mg ] were significantly higher than those in the con- trol group [ （0.45 ±0. 11 ）, （0. 16 ±0.03）, （0. 15 ±0. 02） U/mg] （P =0. 000）. The activity of SOD, CAT and GSH - Px in group B was significantly higher than that in group A （P =0. 019,0.023, 0. 031 ）. The activity of SOD, CAT and GSH - Px in group C was significantly higher than that in group B （ P =0. 001, 0. 017, 0. 006）. There was no significant difference in the activity of SOD, CAT and GSH - Px between group D group C （ P = 0. 198, 0. 347, 0. 269 ） , and between group E and group D （ P = 0. 634, 0. 512, 0. 491 ）. Conclusion The optimal LLLI energy density is 0. 96 J/cm2 in the treatment of rats with acute myocardial infarction.