低强度激光血管外照射对实验兔主动脉粥样硬化病理过程的影响

目的 研究低强度激光（选用激光的波长为650nm、强度为5mW）血管外照射对兔实验性主动脉粥样硬化病理学过程的影响。方法 共选取雄性新西兰大白兔36只，经先期基础喂养1周后给予高脂饮食；然后将其随机分为照射组（给予激光血管外照射）、药物组（给予辛伐他汀治疗）、综合组（给予激光及药物治疗）及对照组。各组动物于第60天实验结束时抽血行血脂测定；于第61天时将其处死，每只动物均切取主动脉组织进行大体及镜下观察，并将各组实验动物动脉粥样硬化程度按正常、轻、中、重度进行评定。结果 实验开始前，4组实验兔血脂水平间差异无统计学意义（P＞0．05）；分别经高脂饲料喂养60d后，照射组、药物组及综合组TG、LDL-C含量与对照组比较，差异均有统计学意义（P＜0．05）；照射组、综合组HDL-C含量与对照组比较，差异亦有统计学意义（P＜0．01）；另外还发现，实验兔主动脉粥样硬化的病理学改变与其血脂变化程度相对应；各治疗组实验动物主动脉粥样硬化程度均以轻度为主，而对照组则以中、重度为主，综合组均为轻度改变，如照射组与药物组中度改变只有1只，对照组不但有1只为重度改变，另还有3只为中度改变。结论 本研究结果表明，无论是单独给予低强度激光照射或他汀类药物治疗或是两者联合治疗，对防治血脂异常所致的动脉粥样硬化均有一定疗效，其中以两者联用效果较佳。

Effects of low-intensity laser irradiation on aortic atherosclerosis in rabbits

Objective To observe the effects of low-intensity(650 nm,5 mW)laser irradiation on the pathological changes associated with aortic atherosclerosis using a rabbit model.Methods Thirty-six male Zelanian rabbits were randomly divided into 4 equal groups:a control group,a laser irradiation group,a simvastatin treatment group and a laser plus simvastatin group,and were treated accordingly.After being fed the basic diet for a week,all the animals were fed a high fat diet during the experiment.Blood samples were taken for lipid assay at the 60th day. The animals were sacrificed at the 61st day and their aortas removed for gross and microscopic examination.Any pathological changes were graded as mild,intermediate or severe according to the indicators of atherosclerosis observed.Results There were no significant differences in blood fat levels among the four groups before the experi- ment,but significant differences in serum triglyceride prevailed after the treatments.Low-density lipoprotein(LDL)- C level in the control group was significantly higher than those in the laser irradiation,simvastatin treatment and laser plus simvastatin groups.There was also a very significant difference in high-density lipoprotein(HDL)-C levels among the laser irradiation group,the laser plus simvastatin group and the control group.The pathological changes observed were correlated with blood fat levels.Mild atherosclerosis was found in the treated groups,but severe or in- termediate atherosclerosis was more prevalent in the control group.Conclusion Low-intensity laser irradiation a- lone or combined with simvastatin can significantly decrease blood lipid levels and the severity of pathological changes associated with aortic atherosclerosis in this animal model.