Which of the following does not increase in response to epinephrine? a. glucose storage b. heart rate c. blood pressure
The correct answer and explanation is:
Correct Answer: a. glucose storage
Epinephrine, also known as adrenaline, is a hormone and neurotransmitter released by the adrenal glands during the body’s fight-or-flight response. Its main role is to prepare the body to respond to stress or danger. To do this, it triggers a series of physiological changes that help increase energy availability and readiness for action.
One of epinephrine’s key actions is to increase blood glucose levels, not to store it. It stimulates processes such as glycogenolysis (the breakdown of glycogen into glucose) in the liver and muscles and gluconeogenesis (the creation of glucose from non-carbohydrate sources). These actions ensure that enough glucose is available in the bloodstream to fuel muscles and vital organs during a stress response. Therefore, glucose storage decreases in response to epinephrine because the hormone promotes glucose release rather than storage.
In contrast, epinephrine increases heart rate by acting on beta-1 adrenergic receptors in the heart. This increases cardiac output and helps supply oxygen and nutrients to muscles more efficiently during stressful situations.
Epinephrine also raises blood pressure, primarily through its action on alpha-1 adrenergic receptors in the blood vessels, leading to vasoconstriction (narrowing of blood vessels). This narrowing raises vascular resistance and, as a result, increases blood pressure.
To summarize, glucose storage does not increase in response to epinephrine. Instead, epinephrine reduces glucose storage by promoting its release into the bloodstream for immediate energy use. Heart rate and blood pressure, on the other hand, both increase as part of the body’s acute stress response to support rapid physical activity or alertness.