Which two anterior pituitary hormones act as insulin antagonists?

• A. ACTH and GH
• B. TSH and LH
• C. Prolactin and FSH
• D. ACTH and TSH

Answer: (A)

Counterregulatory hormones that oppose insulin help keep blood glucose from dropping too low. Growth hormone acts directly as an insulin antagonist by reducing glucose uptake in muscle and fat and increasing hepatic glucose production, which raises blood sugar and opposes insulin’s effects. ACTH’s role is indirect but crucial: it stimulates the adrenal cortex to release cortisol, and cortisol has strong anti-insulin actions—promoting gluconeogenesis, fueling glucose output from the liver, and reducing glucose uptake in peripheral tissues. So, together, Growth Hormone and ACTH (through cortisol) counteract insulin.

The other options don’t fit because their hormones don’t primarily counter insulin in this way—TSH with LH, or prolactin with FSH, aren’t the hormones known for opposing insulin action.