Actions physiologiques du glucagon

Glucagon plays an important role in regulating carbohydrate metabolism in vivo. Its secretion depends on changes in blood substrate concentrations, the insulin level in the islet and neural input to the α cell. Glucagon provides a stimulus to glucose production (glycogenolysis and gluconeogenesis) thereby maintaining a rate required to match the glucose needs of the body. Glucagon's action occurs mainly in the liver, but glucagon receptors can be found in the kidneys and adipose tissue and in extreme circumstances it can stimulate lipolysis. Glucagon is an important regulator in physiological conditions such as fasting, physical exercise and the hypoglycemia. Glucagon levels are elevated in individuals with diabetes and the hormone is felt to contribute to the catabolic consequences of insulin deficiency. As a result pharmaceutical companies are attempting to lower glucagon levels and impair glucagon action as a mean to treat diabetes.