高血压和衰老对冠状动脉重构的影响

The effects of hypertension and aging on coronary arteriolar remodeling

目的：研究高血压和老化对冠状动脉结构和功能的影响。方法：以４，１６，２６，４０，５５周龄的自发性高血压大鼠（ＳＨＲ）和同种系正常血压的京都种大鼠（ＷＫＹ）为动物模型，离体灌注测定冠状动脉最大流量（ＭＣＦ），光镜下测量冠状动脉外径（ＯＤ）、内径（ＬＤ）、冠状动脉壁横截面积（ＣＳＡ）及横截面积和内径比（ＣＳＡ／ＬＤ）。结果：高血压可致冠状动脉ＬＤ显著下降，ＣＳＡ和ＣＳＡ／ＬＤ显著增大；老化对ＬＤ及ＯＤ＜１００μｍ冠状动脉的ＣＳＡ和ＣＳＡ／ＬＤ无显著影响，但可致ＯＤ＞１００μｍ冠状动脉的ＣＳＡ和ＣＳＡ／ＬＤ显著增大；高血压和老化可致ＭＣＦ显著下降，ＭＣＦ与ＯＤ＞１００μｍ冠状动脉的ＣＳＡ／ＬＤ呈显著直线负相关。结论：高血压和老化伴随有冠状动脉结构和功能的改变，ＯＤ＞１００μｍ冠状动脉结构改变可能是冠状动脉功能改变的主要原因。

Objective: To study the effects of hypertension and aging on structure and function of coronary vasculature. Methods: Spontaneously hypertensive rats(SHR) and normotensive Wistar Kyoto rats(WKY) strains at 4,16,26,40, and 55 weeks of age were studied. Maximal coronary flow(MCF) was measured using an isolated perfused rat heart model. Outer dimeter(OD), lumen dimeter(LD), cross sectional area(CSA), and CSA/LD were analysed by computer. Results: LD demonstrated a significant hypertension related decline and was not effected by aging. CSA and CSA/LD in arterioles<100 μm demonstrated a significant hypertension related increase and was not effected by aging. There was a significant hypertension and age related increase in CSA and CSA/LD in arterioles>100 μm. In addition, there was a significant hypertension and age related decline in MCF. The tight linear relation between CSA/LD in arterioles>100 μm and MCF. Conclusion: Both hypertension and aging are accompanied by structural and functional alterations of the cornoary vasculature. Structural alterations in arterioles>100 μm may be the main reason for MCF decrease.