慢性宫内缺氧对子代兔成年期血管内皮舒张功能及内膜病理改变的影响

目的 探讨慢性宫内缺氧对子代兔成年期血管内皮依赖性舒张功能及内膜病理改变的影响.方法 新西兰孕兔16只,分慢性宫内缺氧和非慢性宫内缺氧两组,待分娩后去除雌性,再随机取每只母兔的雄性子代2只,母乳饲养3个月后,慢性宫内缺氧组和非慢性宫内缺氧组子代兔均再分高脂饮食和正常饮食,即得慢性宫内缺氧+高脂饮食组、非慢性宫内缺氧+高脂饮食组、慢性宫内缺氧+普食组和非慢性宫内缺氧+普食组(正常时照组),每组各8只.至6个月末用超声和病理手段检测兔腹主动脉内皮舒张功能和内膜病理变化.结果 慢性宫内缺氧可引起子代兔成年期血清总胆固醇和甘油三酯浓度增高,使主动脉内皮依赖性舒张功能降低(P<0.05),还可导致腹主动脉内膜发生一系列病理改变.慢性宫内缺氧与高脂血症能协同加重上述各观察指标变化(P<0.05)).结论 慢性宫内缺氧引起子代兔成年期腹主动脉内皮依赖性舒张功能降低,是动脉粥样硬化的一个重要因素.经历慢性宫内缺氧的子代兔出生后对高脂饮食损伤更为敏感.

The Effects of Chronic Intrauterine Hypoxia on Endothelium Vascular Relaxation and Pathological Change in Adult Rabbit Offspring

Aim To investigate the effects of chronic intrauterine hypoxia(CIH) on endothelium vascular relaxation and pathological change in adult offspring rabbit. Methods Sixteen New-Zealand rabbits were assigned randomly to two groups:CIH group (12%O2,n=8) and normal oxygen group (21%O2,n=8). After delivery,two male offspring rabbits per litter were selected and breast-fed for 3 months. Then they were randomly separated into high-fat diet and normal diet respectively. Thus 4 groups were got as follow:CIH with high fat diet (CIH+HFD,n=8),Non-CIH with high fat diet (NCIH+HFD,n=8),CIH with normal diet (CIH+ND,n=8) and normal control (n=8). At sixth months of age,offspring rabbits were evaluated for endothelium vascular relaxation of the abdominal aorta by ultrasonoscopy. Abdominal aorta was then taken out and observed by electron microscope and lightmicroscope. Results CIH could result in a series of effects in adult rabbit offspring,such as elevated serum total cholesterol (TC) and triglyceride (TG) level,and attenuated endothelial dependent vasodilation(EDV) of abdominal aorta (P<0.05). There were relevant pathological changes in different groups. All these influences caused by CIH were aggravated significantly when hyperlipemia was imposed (P<0.05). Conclusions CIH cause impaired EDV in adult offspring,which might serve as an important factor that can induce atherosclerosis. The adult offspring rabbit which have ever undergone chronic hypoxia in utero were more sensitive to the impairment of high-fat diet.