Hashimoto M, Akishita M, Eto M, Kozaki K, Ako J, Sugimoto N, Yoshizumi M, Toba K, Ouchi Y
Department of Geriatrics, Faculty of Medicine, University of Tokyo, Japan.
Int J Obes Relat Metab Disord. 1998 May;22(5):477-84. doi: 10.1038/sj.ijo.0800620.
Obesity has been reported to be associated with coronary artery disease and other atherosclerotic diseases. Recently, evidence has accumulated indicating that intra-abdominal visceral fat accumulation contributes to atherogenesis; however, the mechanism underlying this remains to be determined. This study was undertaken to elucidate whether intra-abdominal visceral fat accumulation impairs vascular endothelial function in obese men.
Thirty-eight obese men (body mass index (BMI) > or = 26.0), aged 19-64 y (mean age 37.6 +/- 1.8 y) and 23 age-matched non-obese subjects were examined. According to the ratio of the maximum thickness of preperitoneal fat to the minimum thickness of subcutaneous fat (Pmax/Smin) obtained by longitudinal ultrasound scanning in the subxiphoid region in obese men, we divided obese subjects into two categories; visceral (Pmax/Smin > or = 1; n=23) and subcutaneous type (Pmax/Smin < 1; n=15). To investigate endothelial function, we performed ultrasound measurement of the brachial artery diameter non-invasively both at rest and during reactive hyperaemia in the muscle distal to the brachial artery which causes endothelium-dependent vasodilatation. The brachial diameter change was also measured after sublingual administration of nitroglycerin, which causes endothelium-independent vasodilatation. Flow-mediated diameter (D) increase (%FMD; deltaD/D x 100), in the subjects with visceral type obesity (3.09 +/- 0.43%) was significantly lower than those of the subjects with subcutaneous type obesity and non-obese subjects (7.90 +/- 0.51%, 8.91 +/- 0.44%, respectively, P < 0.01). The magnitude of endothelium-independent vasodilatation by nitroglycerin was similar in all groups. On multiple regression analysis, the Pmax/Smin showed a significant inverse correlation with %FMD.
The subjects with visceral type obesity, rather than those with the subcutaneous type, are associated with impaired flow-mediated endothelium-dependent vasodilatation of the brachial artery.
据报道，肥胖与冠状动脉疾病及其他动脉粥样硬化性疾病相关。最近，越来越多的证据表明，腹内内脏脂肪堆积会促进动脉粥样硬化的发生；然而，其潜在机制仍有待确定。本研究旨在阐明腹内内脏脂肪堆积是否会损害肥胖男性的血管内皮功能。
对38名肥胖男性（体重指数（BMI）≥26.0），年龄在19 - 64岁（平均年龄37.6±1.8岁）以及23名年龄匹配的非肥胖受试者进行了检查。根据通过在肥胖男性剑突下区域进行纵向超声扫描获得的腹膜前脂肪最大厚度与皮下脂肪最小厚度之比（Pmax/Smin），将肥胖受试者分为两类；内脏型（Pmax/Smin≥1；n = 23）和皮下型（Pmax/Smin < 1；n = 15）。为了研究内皮功能，我们在静息状态和肱动脉远端肌肉进行反应性充血（导致内皮依赖性血管舒张）期间，通过超声非侵入性测量肱动脉直径。在舌下含服硝酸甘油（导致非内皮依赖性血管舒张）后也测量肱动脉直径变化。内脏型肥胖受试者的血流介导的直径（D）增加（%FMD；δD/D×100）（3.09±0.43%）显著低于皮下型肥胖受试者和非肥胖受试者（分别为7.90±0.51%和8.91±0.44%，P < 0.01）。硝酸甘油引起的非内皮依赖性血管舒张程度在所有组中相似。在多元回归分析中，Pmax/Smin与%FMD呈显著负相关。
内脏型肥胖受试者而非皮下型肥胖受试者，与肱动脉血流介导的心内皮依赖性血管舒张受损有关。
