Hyperinsulinism of infancy: towards an understanding of unregulated insulin release

Insulin is synthesised, stored, and secreted from pancreatic beta cells. Th ese are located within the islets of Langerhans, which are distributed thro ughout the pancreas. Less than 2% of the total pancreas is devoted to an en docrine function. When the mechanisms that control insulin release are comp romised, potentially lethal diseases such as diabetes and neonatal hypoglyc aemia are manifest. This article reviews the physiology of insulin release and illustrates how defects in these processes will result in the pathophys iology of hyperinsulinism of infancy.