Karpe Fredrik, Fielding Barbara A, Ardilouze Jean-Luc, Ilic Vera, Macdonald Ian A, Frayn Keith N
Oxford Lipid Metabolism Group, Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Infirmary, Oxford OX2 6HE, UK.
J Physiol. 2002 May 1;540(Pt 3):1087-93. doi: 10.1113/jphysiol.2001.013358.
Adipose tissue blood flow (ATBF) rises after nutrient ingestion. It is not clear whether this is due to insulin. The aim of this study was to investigate the role of insulin in the regulation of subcutaneous ATBF. We have investigated the role of insulin in the regulation of ATBF in normal, healthy subjects in a three-step procedure to determine the functional level at which insulin may potentially exert its effect. Fifteen subjects were studied on two occasions. On the first visit, 75 g oral glucose was given. In the second, similar plasma concentrations of insulin and glucose were achieved by dynamic intravenous infusions of insulin and glucose. The increase in ATBF after oral glucose (4.2 +/- 1.4 ml min(-1) (100 g tissue)(-1), P = 0.01) was significantly greater (P < 0.05) than that after intravenous infusions (1.5 +/- 0.6 ml min(-1) (100 g tissue)(-1) P < 0.05). For the local delivery of potentially vasoactive substances and simultaneous measurement of ATBF, we describe a novel combination of methods, which we have called 'microinfusion'. We have used this technique to show that locally infused insulin, even at pharmacological concentrations, had no demonstrable effect on ATBF in nine subjects. We conclude that whilst insulin does not have a direct effect on ATBF, it is likely to be an important mediator, possibly acting via sympathetic activation. In the postprandial state, other candidate peptides and hormones are also likely to play important roles.
营养物质摄入后，脂肪组织血流量（ATBF）会增加。目前尚不清楚这是否归因于胰岛素。本研究的目的是调查胰岛素在皮下脂肪组织血流量调节中的作用。我们采用三步法研究了胰岛素在正常健康受试者脂肪组织血流量调节中的作用，以确定胰岛素可能发挥作用的功能水平。15名受试者接受了两次研究。第一次就诊时，给予75g口服葡萄糖。第二次，通过动态静脉输注胰岛素和葡萄糖达到相似的胰岛素和葡萄糖血浆浓度。口服葡萄糖后脂肪组织血流量的增加（4.2±1.4ml·min⁻¹（100g组织）⁻¹，P = 0.01）显著大于（P < 0.05）静脉输注后的增加（1.5±0.6ml·min⁻¹（100g组织）⁻¹，P < 0.05）。为了局部递送潜在的血管活性物质并同时测量脂肪组织血流量，我们描述了一种新的方法组合，我们称之为“微量输注”。我们使用该技术表明，即使在药理浓度下，局部输注胰岛素对9名受试者的脂肪组织血流量也没有明显影响。我们得出结论，虽然胰岛素对脂肪组织血流量没有直接影响，但它可能是一种重要的介质，可能通过交感神经激活发挥作用。在餐后状态下，其他候选肽和激素也可能发挥重要作用。
