Clinical and Experimental Research Laboratory on Vascular Biology, Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Microvasc Res. 2013 Jan;85:99-103. doi: 10.1016/j.mvr.2012.10.009. Epub 2012 Nov 5.
How cholesterol influences the microcirculation on aging subjects is not well known. This study evaluated moderate hypercholesterolemia effects in, treated or not, lean elderly women on brachial artery reactivity and microcirculatory function using venous occlusion plethysmography (VOP) and nailfold videocapillaroscopy (NVC). Patients (mean age 73 years) were divided into healthy elderly (HE, n=15), treated dyslipidemia with statins during at least 6 months (TDL, n=9) and dyslipidemia (DL, n=9, cholesterol, 257±11 and LDL-cholesterol, 157±24 mg/dl). Young, mean age 23 years, women (YC, n=24), served as controls. Laboratory and anthropometrical analysis, VOP peak forearm blood flow (FBF) during the reactive hyperemia response/baseline FBF (%HYPER) and peak FBF after 0.4 mg sublingual nitroglycerin/baseline FBF (%NITRO) were assessed. NVC capillary density and diameters, maximum red blood cell velocity (RBCV(max)) during reactive hyperemia/baseline RBCV and time to reach RBCV(max) were evaluated. Correlations between %HYPER, %NITRO and plasma cholesterol fractions were performed. Total and LDL-cholesterol were increased only in DL group. Capillary diameters were larger in elderly groups than YC. RBCV(max)/baseline RBCV was reduced in the DL group compared to HE, TDL and YC. %HYPER was lower in DL and normalized in TDL group. YC %HYPER was double of HE. %NITRO decreased from (HE=YC) to TDL and DL groups. There was a significant inverse correlation between LDL-cholesterol, non-HDL-cholesterol and %HYPER/% Nitro. In conclusion, moderate hypercholesterolemia reversibly impaired the vasodilatatory response in the microcirculation but the endothelial-independent vasodilator response to nitroglycerine remained irreversibly lower in healthy aged women.
胆固醇如何影响衰老个体的微循环尚不清楚。本研究使用静脉阻塞体积描记法(VOP)和甲襞微血管镜检查(NVC)评估了中等程度高胆固醇血症对接受或不接受他汀类药物治疗的瘦老年女性肱动脉反应性和微循环功能的影响。患者(平均年龄 73 岁)分为健康老年人(HE,n=15)、至少接受 6 个月他汀类药物治疗的血脂异常患者(TDL,n=9)和血脂异常患者(DL,n=9,胆固醇 257±11 和 LDL-胆固醇 157±24mg/dl)。年轻女性(YC,n=24),平均年龄 23 岁,作为对照组。评估实验室和人体测量分析、反应性充血期间前臂血流(FBF)的 VOP 峰值/基础 FBF(%HYPER)和舌下 0.4mg 硝酸甘油后的 FBF 峰值/基础 FBF(%NITRO)。NVC 毛细血管密度和直径、反应性充血期间最大红细胞速度(RBCV(max)/基础 RBCV 和达到 RBCV(max)的时间。%HYPER、%NITRO 和血浆胆固醇分数之间进行了相关性分析。总胆固醇和 LDL-胆固醇仅在 DL 组中增加。与 YC 相比,老年人组的毛细血管直径较大。与 HE、TDL 和 YC 相比,DL 组的 RBCV(max)/基础 RBCV 降低。DL 组和 TDL 组的%HYPER 降低。YC 的%HYPER 是 HE 的两倍。%NITRO 从(HE=YC)到 TDL 和 DL 组降低。LDL-胆固醇、非 HDL-胆固醇与%HYPER/%Nitro 呈显著负相关。结论:中等程度高胆固醇血症可逆性地损害了微循环的血管扩张反应,但健康老年女性的内皮非依赖性血管扩张剂对硝酸甘油的反应仍不可逆地降低。