Tobin L, Simonsen L, Bülow J
Department of Clinical Physiology and Nuclearmedicine, Bispebjerg Hospital, University of Copenhagen, Copenhagen NV, Denmark.
Clin Physiol Funct Imaging. 2010 Nov;30(6):447-52. doi: 10.1111/j.1475-097X.2010.00964.x. Epub 2010 Aug 22.
The adipose tissue metabolism is dependent on its blood perfusion. During lipid mobilization e.g. during exercise and during lipid deposition e.g. postprandial, adipose tissue blood flow is increased. This increase in blood flow may involve capillary recruitment in the tissue. We investigated the basic and postprandial microvascular volume in adipose tissue using real-time contrast-enhanced ultrasound (CEU) imaging in healthy normal weight subjects. In nine subjects, CEU was performed in abdominal subcutaneous adipose tissue and in the underlying skeletal muscle after a bolus injection of ultrasound contrast agent to establish the reproducibility of the technique. In nine subjects, the effect of an oral glucose load on blood flow and microvascular volume was measured in abdominal subcutaneous adipose tissue and forearm skeletal muscle. ¹³³Xe washout and venous occlusion strain-gauge plethysmography was used to measure the adipose tissue and forearm blood flow, respectively. Ultrasound signal intensity of the first plateau phases was 27 ± dB in the abdominal subcutaneous adipose tissue and 18 ± 2 dB (P < 0.05) in the underlying skeletal muscle. The reproducibility of the measurements was good with a 4% coefficient of variation in both tissues. Blood flow and the change in signal intensity as a measure of the microvascular volume increased significantly and simultaneously in abdominal subcutaneous adipose tissue after glucose intake. The forearm blood flow and muscle signal intensity remained constant. It is concluded that the microvascular volume and changes in volume in abdominal subcutaneous adipose tissue can be assessed using CEU with good reproducibility. Postprandial capillary recruitment takes place in abdominal subcutaneous adipose tissue.
脂肪组织的新陈代谢依赖于其血液灌注。在脂质动员期间，如运动时，以及脂质沉积期间，如餐后，脂肪组织的血流量会增加。这种血流量的增加可能涉及组织中毛细血管的募集。我们使用实时对比增强超声（CEU）成像技术，对健康正常体重受试者的脂肪组织基础微血管容积和餐后微血管容积进行了研究。在9名受试者中，静脉推注超声造影剂后，对腹部皮下脂肪组织和其下方的骨骼肌进行CEU检查，以确定该技术的可重复性。在另外9名受试者中，测量了口服葡萄糖负荷对腹部皮下脂肪组织和前臂骨骼肌血流量及微血管容积的影响。分别使用¹³³Xe洗脱法和静脉阻断应变计体积描记法测量脂肪组织和前臂的血流量。腹部皮下脂肪组织第一个平台期的超声信号强度为27±dB，其下方骨骼肌的超声信号强度为18±2dB（P<0.05）。两种组织测量值的可重复性良好，变异系数均为4%。摄入葡萄糖后，腹部皮下脂肪组织的血流量和作为微血管容积指标的信号强度变化显著且同时增加。前臂血流量和肌肉信号强度保持不变。研究得出结论，使用CEU可以很好地评估腹部皮下脂肪组织的微血管容积及其容积变化，且具有良好的可重复性。餐后腹部皮下脂肪组织会发生毛细血管募集。
