摘要目的 观察尿毒症患者桡动脉的组织学改变,并检测其动脉血管僵硬度变化,探讨导致尿毒症患者中等肌性动脉功能改变的结构基础.方法 尿毒症组患者60例,取动静脉内瘘术时切除的桡动脉段,行HE、Masson染色检测血管结构与胶原蛋白成分改变;免疫组化法检测α-SMA、弹性蛋白、骨桥蛋白(OPN)表达改变;TUNEL法检测细胞凋亡情况;透射电镜检查超微结构改变.对照组为20例健康体检人群.两组患者均行踝臂脉搏波传导速度(baPWV)检测,比较两组间baPWV差异,分析桡动脉组织学改变与baPWV变化的关系.结果 多数尿毒症患者桡动脉内膜有均匀性增厚,其内多数细胞表达α-SMA,少数出现凋亡,基质中较多胶原蛋白,无钙质沉积;中膜增厚,α-SMA表达无明显改变,少数平滑肌细胞凋亡,基质胶原蛋白增加,弹性纤维减少,66.7%患者表达OPN,31.7%患者有明显钙盐沉积;外膜增厚,未见钙质沉积.baPWV检测发现,尿毒症组baPWV为(18.5±3.2)m/s,明显大于对照组[(11.2±2.2)m/s,P＜0.001].相关分析显示,baPWV与中膜厚度、钙化程度、OPN及胶原蛋白表达明显正相关,与弹性蛋白表达明显负相关,与内膜厚度无明显相关.合并糖尿病者发生中膜钙化的危险性的OR值为3.1,发生baPWV明显增加的危险性的OR值为2.3.结论 尿毒症患者桡动脉内膜多明显增生,但与血管僵硬度无明显相关;中膜骨化相关蛋白表达明显增加,30%患者出现明显钙化,伴糖尿病时则更加严重.中膜钙化、胶原蛋白增加、弹性蛋白减少可能是尿毒症患者桡动脉血管僵硬度增加的主要原因.

abstractsObjective To examine the changes of histological parameters of radial artery in uremia,and to explore their effects on arterial stiffness.Methods Sixty uremic patients underwent arteriovenous fistula surgery for hemodialysis and 20 healthy subjects received healthy examination were collected as uremia group and control group, respectively.Segments of radial arteries were obtained from all of uremic subjects and were evaluated by HE, Masson, van Kossa staining and electron microscopy.The expressions of osteopontin (OPN), α-SMA and elastin in arterial wall were detected by immunostaining, and apoptotic cells were determined by TUNEL assay.All of the subjects in the two groups received brachial ankle pulse wave velocity (baPWV) examination and the results were compared.The associations among histological parameters and baPWV were analyzed.Results More than one half (34/60) of artery samples presented uniformly thickening intima, in which most of cells expressed α-SMA and a few cells underwent apoptosis.The subendothelial matrix was abundant in collagen fibers, and no calcium deposition was found.The media thickened obviously, with increased collagen fibers, reduced elastin, unchanged α-SMA expression, and a few apoptotic smooth muscle cells.Two thirds uremic arteries expressed OPN, of which only one half had significant calcium deposition.The adventitia thickened and no calcium deposition was found.The baPWV level in uremic subjects was ( 18.5 ± 3.2 ) m/s, far greater than that in control subjects ( P ＜ 0.001 ).Statistical analysis showed that baPWV value was correlated with media thickness, calcification degree, and collagen content positively, and with elastin expression negatively.For diabetic uremic subjects, the OR values of vascular calcium deposition and remarkably-elevated baPWV value were 3.1, 2.3, respectively.Conclusions Radial arterial intima often presents hyperplasia which is not related with baPWV increment in uremia.Arterial media calcification and collagen content incremental are the most two protuberant characteristics in uremia, especially in ones accompanied with diabetes.Medical calcification, collagen accumulation, and e]astin reduction may contribute to the increased arterial stiffness in uremia.