Section of Molecular Physiology, the August Krogh Centre, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark;
Am J Physiol Endocrinol Metab. 2014 Feb 15;306(4):E355-62. doi: 10.1152/ajpendo.00283.2013. Epub 2013 Dec 3.
The insulinotropic gut hormone glucagon-like peptide-1 (GLP-1) has been proposed to have effects on vascular function and glucose disposal. However, whether GLP-1 is able to increase microvascular recruitment (MVR) in humans has not been investigated. GLP-1 was infused in the femoral artery in overnight-fasted, healthy young men. Microvascular recruitment was measured with real-time contrast-enhanced ultrasound and leg glucose uptake by the leg balance technique with and without inhibition of the insulinotropic response of GLP-1 by coinfusion of octreotide. As a positive control, MVR and leg glucose uptake were measured during a hyperinsulinemic-euglycemic clamp. Infusion of GLP-1 caused a rapid increase (P < 0.05) of 20 ± 12% (mean ± SE) in MVR in the vastus lateralis muscle of the infused leg after 5 min, and MVR further increased to 60 ± 8% above preinfusion levels by 60 min infusion. The effect was slightly slower but similar in magnitude in the noninfused contralateral leg, in which GLP-1 concentration was within the physiological range. Octreotide infusion did not prevent the GLP-1-induced increase in MVR. GLP-1 infusion did not increase leg glucose uptake with or without octreotide coinfusion. GLP-1 infusion in rats increased MVR by 28% (P < 0.05) but did not increase muscle glucose uptake. During the hyperinsulinemic clamp, MVR increased ∼40%, and leg glucose uptake increased 35-fold. It is concluded that GLP-1 in physiological concentrations causes a rapid insulin-independent increase in muscle MVR but does not affect muscle glucose uptake.
肠促胰岛素激素胰高血糖素样肽-1（GLP-1）被认为对血管功能和葡萄糖处置具有作用。然而，GLP-1 是否能够增加人类的微血管募集（MVR）尚未得到研究。在 overnight-fasted 的健康年轻男性中，经股动脉输注 GLP-1。通过实时对比增强超声测量微血管募集，并用和不用奥曲肽共输注抑制 GLP-1 的胰岛素促分泌作用来测量腿部葡萄糖摄取。作为阳性对照，在高胰岛素-正常血糖钳夹期间测量 MVR 和腿部葡萄糖摄取。GLP-1 输注在 5 分钟后引起输注侧股外侧肌 MVR 快速增加（P < 0.05）20 ± 12%（平均值 ± SE），并且 MVR 在 60 分钟输注时进一步增加至高于输注前水平的 60 ± 8%。在未输注的对侧肢体中，效应虽然稍慢，但幅度相似，因为在对侧肢体中 GLP-1 浓度处于生理范围内。奥曲肽输注不能预防 GLP-1 引起的 MVR 增加。GLP-1 输注无论是否共输注奥曲肽都不会增加腿部葡萄糖摄取。GLP-1 输注使大鼠 MVR 增加 28%（P < 0.05），但不会增加肌肉葡萄糖摄取。在高胰岛素钳夹期间，MVR 增加约 40%，腿部葡萄糖摄取增加 35 倍。结论是，在生理浓度下，GLP-1 会引起肌肉 MVR 的快速、胰岛素非依赖性增加，但不会影响肌肉葡萄糖摄取。
