Blood glucose, a primary source of fuel for cells, is maintained within narrow boundaries by hormones. Hormones are chemicals released by cells into the bloodstream to have effects on cells distant from their site of release. In diabetes, the control mechanisms are deficient, resulting in swings in the concentration of blood glucose. The main hormones that regulate blood glucose are released from the cells of the pancreas. Other important hormones include those of the incretin family, and secondary hormones that largely have an effect on the levels of the above hormones.
Alpha Cell Pancreatic Hormones
According to an article written by Dr. Stephen Aronoff et al. published by the American Diabetes Association, special cells in the pancreas called alpha cells release the hormone glucagon. Glucagon raises blood glucose by releasing stored glucose from the liver and causing the liver to synthesize new glucose. Glucose is stored in the liver in long branching chains called glycogen. When blood glucose drops below a set range, glucagon is released from the pancreas. The result is activation of enzymes in the liver that break down glycogen into glucose and replenish glucose levels in the blood.
Beta Cell Pancreatic Hormones
Other special cells within the pancreas called beta cells release insulin. Food is broken down in the intestine and enters the bloodstream, raising the glucose level. Insulin signals the cells in the body to take up the glucose to use it for fuel, so it lowers blood glucose. In addition insulin causes the liver to store glucose as glycogen and inhibits glucagon. The other hormone released by beta cells is amylin, which suppresses glucagon and slows the passage of food from the stomach to the intestine, according to the American Diabetes Association.
Gastrointestinal Hormones
In addition to those in the pancreas, hormones in the gastrointestinal tract regulate blood glucose. These are hormones of the incretin family known as GIP and GLP-1. These hormones are similar, and in humans GLP-1 is thought to be more active, according to The American Diabetic Association. This hormone enhances insulin, suppresses glucagon, slows the passage of food from the stomach to the intestine, and reduces appetite.
Secondary Regulators
Insulin, glucagon, amylin and incretins are the primary hormones that control blood glucose. Secondary regulators of blood glucose affect blood glucose concentration by changing levels of these primary hormones and exerting independent effects. Epinephrine, also known as adrenalin, growth hormone and cortisol all cause the levels of blood glucose to rise, according to the University of California at San Francisco. Other hormones that cause the levels of blood glucose to rise include ACTH, somatostatin and thyroxine, according to Dr. Linda Costanzo's book "Physiology."
