DKA

The pancreatic islets of Langerhans secrete insulin from the B cells. Insulin is secreted initially as a pro-hormone from which C-peptide is cleaved leaving the active insulin hormone.

Insulin actions

Insulin has many actions as shown in the table below. The most well known is the stimulation of glucose and amino-acid uptake from the blood to various tissues. This is coupled with the stimulation of anabolic processes including glycogen, protein and lipid synthesis.

A deficiency in insulin causes an increase in glucagon, catecholamines, cortisol and growth hormone. These hormones stimulate hepatic glucose production via glycogenolysis and gluconeogenesis.

In addition there is a decreased intake of glucose by the cells. This leads to hyperglycaemia, resulting in glycosuria which causes an osmotic diuresis and dehydration.