Growth hormone (GH) exerts several physiological effects in the body. Which of the following is NOT an effect of GH?

• A. Stimulates protein synthesis and promotes tissue growth
• B. Promotes lipolysis in adipose tissue
• C. Directly decreases insulin-like growth factor 1 (IGF-1) production by the liver
• D. Increases blood glucose levels by reducing cellular glucose uptake

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the primary physiological effects of Growth Hormone (GH). GH mainly promotes protein synthesis, tissue growth, and stimulates lipolysis (breakdown of fats) in adipose tissue.
2. Step 2: Recognize that GH indirectly increases insulin-like growth factor 1 (IGF-1) production by stimulating the liver, which then mediates many of GH's growth-promoting effects.
3. Step 3: Note that GH increases blood glucose levels by reducing cellular glucose uptake, which is part of its role in maintaining energy availability.
4. Step 4: Identify the incorrect statement by comparing it to the known effects of GH. Since GH actually increases IGF-1 production, the statement that it directly decreases IGF-1 production by the liver is false.
5. Step 5: Conclude that the option stating GH directly decreases IGF-1 production by the liver is NOT an effect of GH, making it the correct answer to the question.