1型糖尿病早期肱动脉内皮依赖性血管舒张功能已降低

目的　探讨 1型糖尿病(DM)早期患者内皮功能的变化。方法　选择 22例无血管并发症的 1型DM患者和 20名年龄、性别匹配的健康个体。采用高分辨血管外超声法检测肱动脉血流介导的内皮依赖性血管舒张功能和硝酸甘油(GNT)介导的内皮非依赖性血管舒张功能。结果　1型DM组血流介导的血管舒张功能为 3. 83%,明显低于对照组的 4. 87% (P<0. 05)。基础血管内径、基础血流、GNT介导的血管舒张功能在两组间差异无统计学意义(P>0. 05)。结论　早期 1型DM患者就有内皮依赖性血管舒张功能降低。     

女性2型糖尿病患者载脂蛋白e4等位基因与内皮依赖性血管舒张功能降低有关

目的　探讨女性 2型糖尿病患者载脂蛋白e(Apoe)基因型与内皮依赖性动脉舒张功能的关系。方法　选择 101例无血管并发症女性 2型糖尿病患者和 95例年龄匹配的女性健康个体,采用PCR/ASO探针杂交技术检测其Apoe基因型,同时采用高分辨血管外超声法检测肱动脉血流介导的内皮依赖性血管舒张功能和硝酸甘油(GNT)介导的内皮非依赖性血管舒张功能。结果　 (1)不论在女性 2型糖尿病患者还是在对照组,e4 /3、e4 /4基因型携带者内皮依赖性血管舒张功能〔分别为(3. 22±0. 29)%和(3. 78±0. 4)%〕,均低于此 2组的e2 /2、e3 /2携带者〔分别为(3. 96±0. 33)%和(4. 74±0. 41)%,P<0. 05〕。在各基因型间,基础血管内径、基础血流和GNT介导的血管舒张差异无统计学意义。(2)多元逐步回归分析结果显示,在女性 2型糖尿病患者中,年龄、血管内径、低密度脂蛋白胆固醇 (LDL C)、脂蛋白 (a)〔Lp(a)〕、Apoe4、空腹血糖、餐后 2h血糖、HbA1c、病程及阳性心血管病家族史与血流介导的内皮依赖性血管舒张功能均呈负相关(均P<0. 01);在对照组中,血流介导的内皮依赖性血管舒张功能与年龄、血管内径、LDL C、Lp(a)、Apoe4呈负相关(均P<0. 05)。结论　在无血管并发症女性 2型糖尿病患者和健康女性中,Apoe4等位基因与血流介导的内皮依赖     

糖尿病患者内皮tPA、NO储备与血管舒张功能变化

目的　探讨糖尿病患者血管舒张功能和内皮组织纤溶酶原激活物 (tPA)、一氧化氮 (NO)储备释放功能与糖尿病性血管病变的关系。方法　对 15名正常人和 2 3例 2型糖尿病患者 ,采用高频超声方法测定血流介导和硝酸甘油介导的血管舒张功能和颈总动脉内膜厚度 ,以及采用静脉闭塞试验测定tPA和NO储备释放。结果　与正常对照组比较 ,糖尿病组的非内皮依赖性血管舒张功能无显著变化 ,而内皮依赖性血管舒张功能和tPA、NO释放明显低下 (P <0 .0 5或P <0 .0 1) ,颈总动脉内膜增厚 ,但差异无显著性。正常组血tPA水平与NO水平 ,以及tPA释放与NO释放呈显著正相关 ,而糖尿病组收缩压、舒张压均与内皮依赖性血管舒张功能和非内皮依赖性血管舒张功能呈显著负相关。结论　糖尿病患者存在明显的内皮tPA、NO储备释放功能和内皮依赖性舒张功能障碍 ,此与糖尿病性血管病变密切相关     

2型糖尿病病人血管内皮依赖性舒张功能的改变

目的　了解 2型糖尿病病人血管内皮依赖性舒张功能的改变。方法　分别选取对照组、2型糖尿病组及 2型糖尿病合并血脂异常组 ,采用高分辨血管外超声法检测其肱动脉血流介导的内皮依赖性舒张功能和硝酸甘油介导的内皮非依赖性舒张功能。同时测定血脂水平。结果　 12型糖尿病组和 2型糖尿病合并血脂异常组内皮依赖性舒张功能较对照组均明显降低 ( P <0 .0 5) ;2型糖尿病合并血脂异常组较 2型糖尿病组有减退 ,但无显著差异 ( P>0 .0 5)。 2 2型糖尿病合并血脂异常组非内皮依赖性舒张功能较 2型糖尿病组及对照组减退 ,差异显著 ( P<0 .0 5) ;2型糖尿病组与对照组无显著性差异 ( P>0 .0 5)。结论　 2型糖尿病对血管内皮功能有影响 ,且影响因素是多方面的 ,既有糖代谢紊乱因素 ,又有脂代谢紊乱因素     

女性甲减患者甲状腺素治疗改善内皮细胞依赖性血管舒张功能

目的　观察甲状腺功能减退症(甲减)患者甲状腺激素补充治疗后内皮依赖性血管舒张功能的变化。方法　选择初诊的女性临床甲减患者33例、亚临床甲减患者25例及正常健康女性25名。采用高分辨血管外超声法检测肱动脉血流介导的内皮依赖性血管舒张功能和硝酸甘油(GNT)介导的非内皮依赖性血管舒张功能。结果　(1)与对照组比较,临床甲减组和亚临床甲减组治疗前TSH、脂蛋白(a)〔L(a)〕、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL C)水平明显升高,血流介导的血管舒张功能降低(均<0. 05)。(2)与治疗前比较,临床甲减组和亚临床甲减组TSH、Lp(a)、LDL C、载脂蛋白B水平明显降低;血流介导的血管舒张功能明显升高(均P<0. 05)。(3)临床甲减组和亚临床甲减组治疗前后TSH、Lp(a)LDL C的变化与血流介导的血管舒张功能呈负相关(均P<0. 05)。结论　甲减患者内皮依赖性血管舒张功能降低,甲状腺激素补充治疗可改善内皮功能。     

糖尿病不同时期血管内皮依赖性舒张功能变化

目的　探讨糖尿病不同时期血管内皮依赖性舒张功能变化。方法　采用高分辨率血管外彩超,检测33 例对照组和 96 例糖代谢异常者肱动脉内皮依赖性血流介导的血管舒张功能(EDF)。其中糖代谢异常者包括:糖耐量减低组30例、2型糖尿病无血管病变组 30 例和伴血管病变组36例。结果　与对照组(13. 08%±4 .90%)比较,糖耐量减低组已存在 EDF 降低(10 46%±4 54%), 糖尿病患者 EDF 则进一步降低(6 .25%±2 .95%),糖尿病血管病变组患者 EDF 最低[5. 17%±2 .11%;与无血管病变组(7 .59%±3 .29%)比较 t=3 .536, P<0 .01]。结论　在早期糖代谢紊乱即糖耐量减低和无血管病变临床证据的糖尿病患者,利用内皮依赖性血流介导的血管舒张功能检测,可早期发现血管内皮功能受损,这种受损随糖代谢紊乱加重而进一步恶化。     

益多脂对高甘油三酯血症患者血管内皮依赖性舒张功能的影响

目的 :观察益多脂对高甘油三酯血症患者血管内皮依赖性舒张功能的影响。方法 :30例高甘油三酯血症患者 (治疗组 )口服益多脂治疗 8周后 ,采静脉血用酶法测定甘油三酯 (TG)和总胆固醇 (TC)的浓度 ;采用高分辨率血管外超声法检测治疗前后肱动脉内皮依赖性血管舒张功能 ,并与 2 8例正常对照者 (对照组 )比较。结果 :治疗组血流介导的内皮依赖性血管舒张功能明显减弱 ,与对照组相比差异有显著性意义 [(4 .1± 0 .5 ) %∶(10 .1± 0 .8) % ],单因素相关分析发现 :血浆TG浓度与血流介导的肱动脉内皮依赖性舒张功能下降值之间呈负相关 (r =- 0 .6 3,P <0 .0 1)。治疗 8周后血流介导的内皮依赖性血管舒张功能增加 (4 .6± 1.2 ) % (P <0 .0 1) ,单因素相关分析显示 :肱动脉内皮依赖性血管舒张功能改善的程度与TG的基础值无相关性 (r =0 .2 84,P >0 .0 5 ) ,与TG的降低程度呈正相关 (r =0 .5 39,P <0 .0 1)。结论 :益多脂对高甘油三酯血症患者具有改善其血管内皮依赖性舒张功能的作用     

2型糖尿病患者血管舒张功能和一氧化氮释放变化及与动脉硬化的关系

目的　探讨 2型糖尿病患者血管舒张功能和一氧化氮释放与糖尿病血管病变的关系。方法　选择 2 0名正常人 (对照组 )和 62例 2型糖尿病患者 (糖尿病组 ) ,并根据患者是否合并冠心病进行分组分析。采用高频超声方法测定反应性充血试验和口服硝酸甘油前后的肱动脉内径变化 ,以反映血管内皮依赖性和非内皮依赖性舒张功能 ,以及静脉闭塞试验测定一氧化氮储备释放 ,同时利用超声方法检测颈总动脉内膜厚度。结果　与对照组比较 ,糖尿病组的非内皮依赖性血管舒张功能无显著变化 (P >0 .0 5 ) ,而内皮依赖性血管舒张功能和内皮一氧化氮释放明显低下 (P<0 .0 5～ 0 .0 1) ,颈总动脉内膜厚度明显增厚 (P <0 .0 1)。糖尿病合并冠心病患者血管内皮依赖性和非内皮依赖性舒张功能均较非合并冠心病患者明显低下。结论　高频超声检测方法能够较好地判断糖尿病患者血管舒张功能。糖尿病患者存在明显的动脉硬化和因一氧化氮释放减少而出现的内皮依赖性舒张功能障碍 ,此与糖尿病性血管病变密切相关     

糖尿病不同时期血管内皮依赖性舒张功能变化

目的探讨糖尿病不同时期血管内皮依赖性舒张功能变化.方法 采用高分辨率血管外彩超,检测33例对照组和96例糖代谢异常者肱动脉内皮依赖性血流介导的血管舒张功能(EDF).其中糖代谢异常者包括糖耐量减低组30例、2型糖尿病无血管病变组30例和伴血管病变组36例.结果 与对照组(13.08%±4.90%)比较,糖耐量减低组已存在EDF降低(10.46%±4.54%), 糖尿病患者EDF则进一步降低(6.25%±2.95%),糖尿病血管病变组患者EDF最低[5.17%±2.11%;与无血管病变组(7.59%±3.29%)比较t=3.536, P<0.01].结论 在早期糖代谢紊乱即糖耐量减低和无血管病变临床证据的糖尿病患者,利用内皮依赖性血流介导的血管舒张功能检测,可早期发现血管内皮功能受损,这种受损随糖代谢紊乱加重而进一步恶化.     

经皮冠状动脉介入治疗对急性冠状动脉综合征患者内皮功能的影响

目的了解急性冠状动脉综合征患者的内皮功能及经皮冠状动脉介入治疗对内皮功能的影响。方法共入选120例急性冠状动脉综合征患者及30例正常对照者,采用高分辨率彩色多普勒超声仪,测定肱动脉内皮依赖性血流介导的血管舒张功能及非内皮依赖性硝酸甘油介导的血管舒张功能。急性冠状动脉综合征患者按有无接受经皮冠状动脉介入治疗分为两组,观察两组患者基线及3个月的内皮依赖性血流介导及非内皮依赖性硝酸甘油介导的血管舒张功能。结果急性冠状动脉综合征患者的内皮依赖性血流介导的血管舒张功能明显低于正常对照组(8.29±5.11比10.64±3.82,P=0.029),而两组间非内皮依赖性硝酸甘油介导的血管舒张功能无明显差别(20.37±9.29比18.41±5.83,P=0.226);经皮冠状动脉介入治疗组术后3个月的内皮依赖性血流介导的血管舒张功能较术前明显降低(5.26±7.20比7.86±5.51,P=0.037),而药物治疗组的内皮依赖性血流介导的血管舒张功能前后对比无明显变化(7.14±6.99比7.91±4.52,P=0.401);内皮依赖性血流介导的血管舒张功能在两组之间及各组治疗前后无统计学差别(P>0.05)。结论急性冠状动脉综合征患者存在内皮功能受损;经皮冠状动脉介入治疗进一步加重内皮功能障碍。     

Apo e4 allele is associated with endothelium-dependent arterial dilation in women with type 2 diabetes

OBJECTIVE: Previous studies have suggested that the e4 allele of apolipoprotein E (apo E) relates to the endothelium-dependent arterial dilation in men with type 2 diabetes. This study attempted to assess whether apo e4 allele is associated with endothelial dysfunction in women with type 2 diabetes. RESEARCH DESIGN AND METHODS: We selected 144 Chinese Han female type 2 diabetic patients without clinically detectable angiopathy. Polymerase chain reaction/ASO probes were used to determine their mouthwash DNA apo E genotypes, and high-resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (with increased flow causing endothelium-dependent dilation) and after sublingual glyceryltrinitrate (GTN, an endothelium-independent dilator). RESULTS: The flow-mediated arterial dilation among the subjects with e4/3 or e4/4 was 3.56+/-0.23%, which was significantly lower than that in subjects with e2/2 or e3/2 (3.97+/-0.36%) (p=0.000). The baseline vessel size, GTN-induced dilation and baseline blood flows were not significantly different among different apo E genotypes. On univariate analysis, reduced flow-mediated arterial dilation was significantly related to total cholesterol, LDL, Lp(a), high blood pressure, older age, family history of premature vascular disease, larger vessel size, duration of diabetes and e4 allele (p<0.05). By multiple stepwise regression analysis, reduced flow-mediated arterial dilation was associated with older age, large vessel size, duration of diabetes, positive family history, LDL, Lp(a) and e4 allele (p<0.01). CONCLUSION: The apo e4 allele is associated with impairment of endothelium-dependent arterial dilation in the relatively early stage of female type 2 diabetes.     

甲状腺功能正常的桥本氏病患者肱动脉内皮依赖性血管舒张功能研究

目的探讨甲状腺功能正常的桥本氏病患者内皮依赖性血管舒张功能的变化。方法选择甲状腺功能正常的女性桥本氏病患者28例(HT甲功正常组),甲状腺功能减低的女性桥本氏病患者23例(HT甲减组)、正常女性22例(对照组)及甲状腺机能亢进症患者11例(甲亢组)。采用高分辨血管外超声法检测肱动脉内皮依赖性血管舒张功能和内皮非依赖性血管舒张功能。结果HT甲功正常组内皮依赖性血管舒张功能为3.88%,明显低于对照组的4.98%(P<0.01),而又明显高于HT甲减组3.26%(P<0.01)。同时,HT甲减组内皮依赖性血管舒张功能明显低于对照组(P<0.01)。甲亢组内皮依赖性血管舒张功能为10.42%,基础血流量为114.5 m l/m in,明显高于其它3组。4组间内皮非依赖性血管舒张功能、基础血管内径相似(P>0.05)。结论甲状腺功能正常的桥本氏病患者内皮依赖性血管舒张功能降低。     

糖耐量减低患者联合干预治疗前后内皮依赖性血管舒张功能的变化

目的为了探讨糖耐量减低(IGT)患者联合干预治疗前后内皮功能的变化。方法选择28例IGT患者,和年龄、性别匹配的健康个体25人。IGT患者采用控制饮食、规则的有氧运动及口服二甲双胍联合干预治疗12周。采用高分辨血管外超声法检测肱动脉内皮依赖性血管舒张功能和内皮非依赖性血管舒张功能。结果IGT患者干预治疗前内皮依赖性血管舒张功能为3.50%,明显低于对照组的4.68%(P<0.05)。多元逐步回归分析结果显示,内皮依赖性血管舒张功能与年龄、LDL-C、Lp(a)、HbA1c、FPG及2hPG呈负相关(P<0.001)。经联合干预治疗12周后,内皮依赖性血管舒张功能明显增高,达到4.17%,明显高于IGT患者干预治疗前(P<0.05)。Spearman分析结果显示,治疗前后内皮依赖性血管舒张功能的变化与FBG、2hBG、LDL-C、HbA1c的变化呈负相关(P<0.05)。结论IGT患者内皮依赖性血管舒张功能降低。联合干预治疗可改善血管内皮功能。     

Acute hyperglycemia rapidly suppresses endothelium-dependent arterial dilation in first-degree relatives of type 2 diabetic patients.

OBJECTIVE: Previous studies showed that endothelium-dependent arterial dilation is impaired in first-degree relatives of type 2 diabetes in the fasting state. In the present study, we examined whether endothelial dysfunction occurs when acute hyperglycemia is induced by oral glucose loading in this cohort. PATIENTS AND METHODS: This study included 32 normal glucose tolerant subjects. Of them, 17 with a family history (FH) of type 2 diabetic parents (FH+) and 15 with no first-degree relative with diabetes or coronary artery disease (FH-). The examination of vascular function was performed in fasting state and repeated 1 and 2 hours after a 75-g oral glucose loading by high resolution ultrasound. RESULTS: Endothelium- dependent arterial dilation in FH+ group were significantly lower than those in FH- before and after oral glucose loading (5.12+/-0.61% vs 6.03+/-0.56%, fasting; 4.0+/-0.65% vs 5.70+/-0.42%, 1 h; 4.43+/-0.61% vs 5.82+/-0.67% 2 h, p<0.05 each). In FH+ group, endothelium-dependent arterial dilation decreased significantly at 60 min (4.0+/-0.65% vs 5.12+/-0.61%, p<0.01) and increased markedly from 60 min at 120 min (4.43+/-0.61% vs 4.0+/-0.65%, p<0.05), which was still significantly lower than baseline (4.43+/-0.61% vs 5.12+/-0.61%, p<0.01) . In FH- group, however, the arterial dilation did not differ significantly among the three time points (p 0.05). In multiple regression analysis, endothelium-dependent arterial dilation was significantly correlated to FH+(r=-0.302, p<0.01). In addition, endothelium-dependent arterial dilation showed a correlation with plasma glucose (r=-0.460, p<0.01) and TBARS (r=-0.382, p<0.01) during OGTT in FH+ subjects. CONCLUSION: Significant endothelial dysfunction is present in the fasting state, hyperglycemia in response to oral glucose loading rapidly suppresses endothelium-dependent arterial dilation in FH+ subjects, probably through increased production of oxygen-derived free radicals.     

Changes in endothelium-dependent arterial dilation before and after subtotal thyroidectomy in subjects with hyperthyroidism

OBJECTIVE: This case-control study was carried out to assess the alteration of endothelium-dependent arterial dilation before and after subtotal thyroidectomy in subjects with hyperthyroidism. PATIENTS AND METHODS: The study subjects included 12 patients with hyperthyroidism and 39 apparently healthy individuals. We performed a subtotal thyroidectomy on the hyperthyroid patients. The endothelium-dependent arterial dilation was determined with a high-resolution ultrasound method in each patient at the hyperthyroid stage before treatment (stage H), the euthyroid stage induced immediately before surgery (stage E), and the transient hypothyroid stage 1 or 2 months after surgery (stage L). RESULTS: The flow-mediated arterial dilation decreased significantly from H to E and from E to L (P < 0.001). As compared with H, baseline blood flow decreased markedly at stages E and L (P < 0.001). The flow-mediated arterial dilation and baseline blood flow in the control subjects were very close to those at stage E of the hyperthyroid patients. The absolute change in the flow-mediated arterial dilation showed significant negative correlation with the changes in TSH (r =-0.86, P < 0.001), lipoprotein (a) [Lp(a)] (r =-0.77, P < 0.001) and low density lipoprotein (LDL) (r =-0.79, P < 0.001), and significant positive correlation with changes in fT3 (r =+0.88, P < 0.001). The absolute change in the baseline blood flow showed significant positive correlation with the change in fT3 (r =+0.85, P < 0.001) and significant negative correlation with the change in TSH (r =-0.63, P < 0.01). CONCLUSION: The endothelium-dependent arterial dilation increases significantly in untreated hyperthyroid patients, and decreases markedly after a subtotal thyroidectomy. Therefore, we conclude that the endothelium is more responsive to reactive hyperaemia in the hyperthyroid than the euthyroid state.     

急性高血糖对肱动脉内皮依赖性血管舒张功能影响的研究

目的 探讨葡萄糖负荷试验所致急性高血糖对血管内皮功能的影响。方法 选择正常健康人（NC）、糖耐量减低（IGT）患者和2型糖尿病（T2DM）患者各10例。所有对象均做OGTT，分别于0、60、120min采用高分辨血管外超声检测肱动脉血流介导的内皮依赖性血管舒张功能和硝酸甘油（GNT）介导的内皮非依赖性血管舒张功能。结果 IGT组和T2DM组0、60、120min的内皮依赖性血管舒张功能均明显低于NC组（P〈0．05）。与0min相比，IGT组和T2DM组60min内皮依赖性血管舒张功能明显降低，120min又回升，明显高于60min者（P〈0．05）。IGT组和T2DM组在基础状态下，LDL-C、Lp（a）、FPG、HbA-C与内皮依赖性血管舒张功能呈负相关（P〈0．01）。在OGTT中，这两组血糖与内皮依赖性血管舒张功能呈负相关（P〈0．001）。结论 高血糖快速抑制内皮依赖性血管舒张功能。提示餐后高血糖在糖尿病血管并发症的发生与发展中起重要作用。     

Changes of osteoprotegerin before and after insulin therapy in type 1 diabetic patients

OBJECTIVE: Osteoprotegerin (OPG) regulates osteoclast and immune functions and appears to represent a protective factor for vascular system. However, the role of OPG in endothelial dysfunction of type 1 diabetic patients has not been evaluated. The purpose of this study was to investigate the relationship between plasma OPG levels and endothelium-dependent arterial dilation in type 1 diabetic patients. RESEARCH DESIGN AND METHODS: This study subjects included 22 newly diagnosed type 1 diabetic patients and 28 healthy subjects. All patients were then given insulin therapy for 6 months. Plasma OPG concentration was measured in duplicate by a sandwich ELISA method, and high-resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia and after sublingual glyceryltrinitrate (GTN). RESULTS: Plasma OPG level in patients before treatment was 3.09+/-0.70 ng/L, which was significantly higher than that in control (2.07+/-0.75 ng/L) (p<0.001). After 6 months treatment, OPG levels decreased markedly (2.58+/-0.59 ng/L) (p<0.001). The flow-mediated endothelium-dependent arterial dilation in patients before treatment was 3.35+/-0.67%, which was significantly lower than that in control (5.17+/-0.83%) (p<0.001), and improved markedly after 6 months treatment (4.27+/-0.63%) (p<0.001). In multivariate analysis, OPG was significantly associated with endothelium-dependent arterial dilation, fasting blood glucose (FBG), hemoglobin A1c (HbA1c), and ultra sensitive C-reactive protein (CRP) at baseline (p<0.01). The absolute changes in OPG showed significant correlation with the changes in endothelium-dependent arterial dilation, FBG, HbA1c, and CRP in diabetic patients during the course of treatment (p<0.01). CONCLUSION: This study shows that plasma OPG levels are elevated in newly diagnosed type 1 diabetic patients, and that plasma OPG levels are significantly associated with endothelial function.     

Apolipoprotein e4 allele and endothelium-dependent arterial dilation in Type 2 diabetes mellitus without angiopathy

AIMS/HYPOTHESIS: Several studies have suggested a predisposing role of the e4 allele of apolipoprotein E (ApoE) in the development of atherosclerosis and cardiovascular disease in Type 2 diabetes. Therefore, we hypothesized that the e4 allele is also a risk factor for endothelial dysfunction. We attempted to assess whether Apo e4 allele is associated with endothelial dysfunction in the early stage of Type 2 diabetes. METHODS: We selected 255 Chinese Han Type 2 diabtetic men without angiopathy. PCR or allele-specific oligonucleotide probes were used to analyse ApoE genotypes, and high resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperaemia and after sublingual glyceryltrinitrate. RESULTS: The flow-mediated arterial dilation among the subjects with e4/3 or e4/4 was 3.14+/-0.32%, which was lower than that in subjects with e2/2 or e3/2 (4.04+/-0.30%) ( p=0.038). The baseline vessel size, glyceryltrinitrate-induced arterial dilation and baseline flow were not different among different ApoE genotypes. On univariate analysis, reduced flow-mediated arterial dilation was related to total cholesterol, LDL, lipoprotein(a) [Lp(a)], high blood pressure, older age, family history of premature vascular disease, larger vessel size, cigarette smoking, duration of diabetes and e4 allele ( p<0.05). By multiple stepwise regression analysis, reduced flow-mediated arterial dilation was associated with cigarette smoking, LDL, Lp(a), and e4 allele ( p<0.01). CONCLUSION/INTERPRETATION: Apo e4 allele is associated with impairment of endothelium-dependent arterial dilation in the early stage of Type 2 diabetes.     

Impairment of endothelium-dependent arterial dilation in Hashimoto's thyroiditis patients with euthyroidism

OBJECTIVE: Recent studies have shown that immune responses contribute to atherosclerosis, and endothelial dysfunction is an important early event in atherogenesis. The aim of this study was to investigate the alteration of endothelial function in Hashimoto's thyroiditis (HT) patients with euthyroidism. METHODS: Study subjects included 28 female HT patients with euthyroidism, 23 female HT patients with hypothyroidism, and 22 healthy women. High-resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperaemia and after sublingual glyceryltrinitrate (GTN). RESULTS: Flow-mediated arterial dilation in HT patients with euthyroidism was significantly lower (3.88%) than in controls (4.98%, P = 0.000) and higher than in HT patients with hypothyroidism (3.26%, P < 0.001). Flow-mediated arterial dilation among HT patients with hypothyroidism was significantly lower than that in controls (P = 0.000). GTN-induced arterial dilation, baseline vessel size, and baseline blood flow were not significantly different among the three groups (P > 0.05). On multiple regression analysis, anti-thyroid peroxidase antibody (TPO-Ab), TSH, free T3, low density lipoprotein cholesterol (LDL-C) and lipoprotein (a) [Lp(a)] were found to be significant factors associated with endothelium-dependent arterial dilation. CONCLUSION: Endothelial dysfunction exists in HT patients with euthyroidism. Autoimmune reactivity and an elevated Lp(a) level might be responsible for the endothelial dysfunction.