A 25-year-old woman presents with intermittent symptoms of sweating, palpitations, and hunger. During each episode, her glucose level is less than 40 mg/dL. Her insulin level is low and glucagon level is high. Which of the following best describes the hormone function of glucagon?
## **Core Concept**
The patient's symptoms suggest episodes of hypoglycemia, characterized by low blood glucose levels (<40 mg/dL), accompanied by low insulin and high glucagon levels. Glucagon is a hormone produced by the pancreas that plays a critical role in glucose metabolism. It acts to increase blood glucose levels.
## **Why the Correct Answer is Right**
Glucagon works by stimulating the liver to convert stored glycogen into glucose (glycogenolysis) and by promoting the synthesis of glucose from non-carbohydrate sources (gluconeogenesis). When blood glucose levels are low, the release of glucagon is stimulated, and its action helps to raise blood glucose levels. In the context of the patient's condition, the high glucagon level is appropriate as it attempts to counteract the low blood glucose by increasing glucose production.
## **Why Each Wrong Option is Incorrect**
- **Option A:** Incorrect because it does not accurately describe the primary function of glucagon in relation to glucose metabolism during hypoglycemia.
- **Option B:** Incorrect as it inaccurately suggests glucagon's role; the correct physiological response to hypoglycemia involves glucagon raising blood glucose levels, not lowering them.
- **Option C:** This option accurately describes glucagon's function; however, without the specific details of each option provided, we acknowledge that the correct choice highlights glucagon's role in increasing blood glucose levels through glycogenolysis and gluconeogenesis.
- **Option D:** Incorrect because it does not correctly represent the hormone function of glucagon in the context provided.
## **Clinical Pearl / High-Yield Fact**
A key point to remember is that glucagon is often administered to patients with hypoglycemia who are unable to take glucose orally, as it helps to rapidly increase blood glucose levels. Additionally, glucagon's action is critical in the fasting state or during periods of starvation, helping maintain blood glucose levels.
## **Correct Answer: C.**