Pancreatic Physiology

Abstract

The human pancreas consists of two organs in one structure: the exocrine gland made up of pancreatic acinar cells and duct cells that produce digestive enzymes and sodium bicarbonate, respectively; the endocrine gland made up of four islet cells, namely alpha-, beta-, delta-, PP-, and ipsilon- cells that produce glucagon, insulin, somatostatin, pancreatic polypeptide, and ghrelin respectively. While the physiological role of exocrine pancreas (>80 % by volume) is to secrete digestive enzymes responsible for our normal digestion, absorption and assimilation of nutrients, the endocrine pancreas (<2 % by volume) is to secrete islet peptide hormones for the maintenance of our glucose homeostasis. The pancreatic functions are finely regulated by neurocrine, endocrine, paracrine and/or intracrine mechanisms. Thus, dysregulation of these pathways should have significant impacts on our health and disease. Nevertheless, the underlying mechanisms by which pancreatic functions are regulated remain poorly understood.