CAJ | 학술논문

目的探讨长期体外反搏对高胆固醇血症猪颈动脉内膜形态和内皮依赖血管舒张功能的影响.方法 18头雄性乳猪被随机分为3组,每组6只.用喂养高脂饲料乳猪复制高胆固醇血症模型(高脂饲养组);采用增强型体外反搏(EECP)治疗模型动物36 h(EECP组);以正常饲养组作为对照.取各组动物颈总动脉血管.用扫描电镜和透射电镜观察颈动脉内膜的形态,并测定离体颈动脉血管环对不同浓度梯度乙酰胆碱(Ach)的舒张反应.结果扫描电镜下观察高脂饲养组血管内皮细胞排列紊乱,内皮细胞有明显脱落,部分细胞胞膜皱缩.体积明显减小,符合凋亡细胞的外形特征;EECP组血管内皮细胞排列紊乱的情形明显减轻,内皮细胞大小不一的程度减轻,皱缩脱落细胞较高脂饲养组明显减少.透射电镜下观察高脂饲养组血管内皮细胞凋亡、脱落,内膜破损明显,平滑肌细胞侵入和增生,泡沫细胞形成;EECP组内皮细胞呈梭形,内皮完整,内皮与内皮下结构连接紧密,平滑肌细胞轻度增生,少见泡沫细胞.在10-8～10-5mol/L Ach时,高脂饲养组和EECP组的血管舒张率较正常饲养组显著降低(P均＜0.05);在10-7～10-5mol/L Ach时,EECP组的血管舒张率较高脂饲养组明显提高(P均＜0.05).结论高胆固醇血症动物颈动脉内皮超微结构改变提示有动脉粥样硬化形成,内皮依赖血管舒张功能明显受损;长期EECP干预可以显著改善内皮结构损伤和内皮依赖血管舒张功能,这可能是其发挥抗动脉粥样硬化作用的机制之一.
목적 탐토장기체외반박대고담고순혈증저경동맥내막형태화내피의뢰혈관서장공능적영향.방법 18두웅성유저피수궤분위3조,매조6지.용위양고지사료유저복제고담고순혈증모형(고지사양조);채용증강형체외반박(EECP)치료모형동물36 h(EECP조);이정상사양조작위대조.취각조동물경총동맥혈관.용소묘전경화투사전경관찰경동맥내막적형태,병측정리체경동맥혈관배대불동농도제도을선담감(Ach)적서장반응.결과 소묘전경하관찰고지사양조혈관내피세포배렬문란,내피세포유명현탈락,부분세포포막추축.체적명현감소,부합조망세포적외형특정;EECP조혈관내피세포배렬문란적정형명현감경,내피세포대소불일적정도감경,추축탈락세포교고지사양조명현감소.투사전경하관찰고지사양조혈관내피세포조망、탈락,내막파손명현,평활기세포침입화증생,포말세포형성;EECP조내피세포정사형,내피완정,내피여내피하결구련접긴밀,평활기세포경도증생,소견포말세포.재10-8～10-5mol/L Ach시,고지사양조화EECP조적혈관서장솔교정상사양조현저강저(P균＜0.05);재10-7～10-5mol/L Ach시,EECP조적혈관서장솔교고지사양조명현제고(P균＜0.05).결론 고담고순혈증동물경동맥내피초미결구개변제시유동맥죽양경화형성,내피의뢰혈관서장공능명현수손;장기EECP간예가이현저개선내피결구손상화내피의뢰혈관서장공능,저가능시기발휘항동맥죽양경화작용적궤제지일.
Objective To explore the effect of long-term enhanced external counterpulsation (EECP) on morphological damage of endomembrane and endothelium-dependent vasodilatation of the carotid arteries of hypercholesterolemic pigs.Methods Eighteen male infant pigs were randomly divided into three groups according to the contents of their diet: the normal control group (n=6),the high-cholesterol feeding control group (n=6) and EECP group (n=6).Porcine model of hypercholesterolemia was reproduced by feeding animals with high-cholesterol diet.After completion of EECP treatment for 36 hours in EECP group,carotid arterial rings were harvested from all animals.Both scanning and transmission electron microscopy was employed to observe the changes in morphology of their endomembrane. At the same time, their vasodilatation response to variant dose of acetylcholine (Ach) was detected. Results The surface of endothelium in the normal control group was smooth,and endothelial cells were in regular streamline array,and they were almost in same size,attaching closely to matrix without smooth muscle cell proliferation and lipid infiltration in intima.In contrast,the endothelial cells of hypercholesterolemic pigs were in irregular array,with marked desquamation,resulting in loose linkage.Smooth muscle ceils were found to invade into intimal layer and proliferated,and foam cells could also be found in intimal layer.In hypercholesterolemic pigs treated with EECP,slight intimal damage was found.In addition,with Ach dose of 10-8 mol/L to 10-5 mol/L,endothelium-dependent vasodilatation ratio in hypercholesterolemic pigs with or without EECP treatment,was significantly lower than that of the normal control group (all P＜ 0.05). However,endothelium-dependent vasodilatation ratio in pigs with EECP treatment was obviously higher compared with hypercholesterolemic pigs without EECP treatment with the dosage of Aeh concentration ranged from 10-7 mol/L to 10-5 mol/L (all P＜0.05).Conclusion Long-term EECP ameliorates both the morphological damage and the impaired endothelium-dependent vasodilatation function resulting from hypereholesterolemia,contributing to prevention of atherosclerosis.