Final answer:
Epinephrine and norepinephrine are released during stress and work to increase blood glucose levels, which results in the inhibition of insulin secretion and action. They promote glycogen breakdown and glucose release from the liver, counteracting insulin's role in reducing blood glucose levels.
Step-by-step explanation:
Effects of Epinephrine and Norepinephrine on Insulin
Epinephrine and norepinephrine are hormones released by the adrenal medulla during stress, often referred to as the 'fight-or-flight' hormones. These hormones affect insulin secretion and action in various ways. When the body is under stress, epinephrine and norepinephrine increase blood glucose levels by stimulating the liver and skeletal muscles to break down glycogen and by promoting glucose release by liver cells. Consequently, these hormones contribute to a decrease in insulin secretion. This is partly because epinephrine inhibits insulin secretion through a decrease in cAMP levels within the pancreatic beta cells. The overall effect is to preserve blood glucose for energy, prioritizing it for essential organs like the heart and brain during a stress response.
The secretion of hormones like insulin from the pancreatic islets plays a crucial role in glucose metabolism. Insulin promotes the uptake of glucose by cells, reducing blood glucose levels, and supports the conversion of excess glucose into glycogen for storage. However, in the presence of epinephrine and norepinephrine, there is a shift towards glycogenolysis (breakdown of glycogen) and gluconeogenesis (production of new glucose), which is counteractive to insulin's effects.