The vascular network supporting the islets of Langerhans represents a highly specialised system of arterioles, capillaries and venules. Several features of the islet vasculature (density and fenestration of the capillaries) ensure rapid exchange of nutrients and hormones, which is central to the islets' capacity to control of systemic metabolism via reciprocal changes of insulin and glucagon secretion. Here we discuss how changes in islet blood flow may underlie pulsatile insulin secretion, which becomes impaired in type-2 diabetes. Improved understanding of the architecture and regulation of pancreas/islet blood flow may therefore illuminate the causes underlying this common metabolic disorder. The pioneering work of August Krogh on blood flow, oxygen diffusion and capillary anatomy (that was awarded with the Nobel Prize in 1920) is a cornerstone in these efforts and remains relevant to today's research.

支持Langerhans胰岛的血管网络代表着高度专业化的小动脉，毛细血管和小静脉系统。胰岛脉管系统的几个特征（毛细血管的密度和开窗）确保营养物质和激素的快速交换，这对胰岛通过胰岛素和胰高血糖素分泌的相互变化控制系统代谢的能力至关重要。在这里，我们讨论了胰岛血流的变化如何可能是搏动性胰岛素分泌的基础，而后者在2型糖尿病中变得受损。因此，对胰腺/胰岛血流的结构和调节的更好理解可以阐明这种常见的代谢紊乱的原因。August Krogh在血液流动方面的开拓性工作，