The islets of Langerhans make up only an estimated 1-2% of the total pancreas, but receive up to 20% of the blood supply. The abundant vascular blood supply to the pancreas derives from the splenic artery, allowing islets to be easily exposed to systemic blood glucose levels. Interestingly, recent studies suggest that islet local blood flow is tightly regulated by percentage. It dynamically controls the diameter of the islet microvasculature. Under diabetic conditions, pericytes are significantly lost, impairing the fine-tuning of islet function by this mechanism, suggesting a contribution to the pathology of the disease. Adult mice and the human pancreas also differ in innervation. Although the islets of mice have an extensive network of bifurcated nerves that are in direct contact with endocrine cells, the islets of humans are sparsely nerved compared to nerves that are in contact with smooth muscle cells of blood vessels rather than endocrine cells. It is dominated. This supports a new hypothesis that in human’s regulation of islet function depends on dynamic control of blood flow rather than direct signals from the autonomic nervous system.
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