Which hormone is primarily responsible for raising blood glucose during acute stress?

Which hormone is primarily responsible for raising blood glucose during acute stress?

• A. Growth hormone
• B. Epinephrine
• C. Cortisol
• D. Insulin

Answer: (B)

During acute stress, the body relies on a rapid mobilization of energy driven by epinephrine. This hormone, released from the adrenal medulla in the fight-or-flight response, quickly elevates blood glucose by stimulating hepatic glycogenolysis—the breakdown of glycogen to glucose in the liver. It also promotes gluconeogenesis and temporarily suppresses insulin release, reducing glucose uptake by tissues and keeping more glucose in the bloodstream for immediate use. Other hormones like cortisol and growth hormone can raise glucose, but their effects are slower and more sustained, not the immediate spike needed during acute stress. Insulin would counteract a rise in glucose, so it isn’t responsible. Thus epinephrine is the primary driver of the rapid increase in blood glucose during acute stress.

During acute stress, the body relies on a rapid mobilization of energy driven by epinephrine. This hormone, released from the adrenal medulla in the fight-or-flight response, quickly elevates blood glucose by stimulating hepatic glycogenolysis—the breakdown of glycogen to glucose in the liver. It also promotes gluconeogenesis and temporarily suppresses insulin release, reducing glucose uptake by tissues and keeping more glucose in the bloodstream for immediate use. Other hormones like cortisol and growth hormone can raise glucose, but their effects are slower and more sustained, not the immediate spike needed during acute stress. Insulin would counteract a rise in glucose, so it isn’t responsible. Thus epinephrine is the primary driver of the rapid increase in blood glucose during acute stress.