The vascular order of islet cellular perfusion in the human pancreas.

The vascular order of pancreatic islet cellular perfusion is important in the intraislet regulation of hormone secretion. Establishment of the sequence of interaction is fundamental to understanding the physiology and pathophysiology of the human islet. Intraislet insulin from the beta-cell regulates both net hormone secretion and pulsatile secretion from alpha- and delta-cells. In terms of vascular perfusion, the delta-cell is perfused last and does not directly affect alpha- or beta-cells in humans.