Which hormone is responsible for acromegaly when secreted in excess?

Which hormone is responsible for acromegaly when secreted in excess?

• A. Prolactin
• B. Thyroid-Stimulating Hormone
• C. Adrenocorticotropic Hormone
• D. Growth Hormone

Answer: (D)

Excess growth hormone drives acromegaly. Growth hormone exerts its effects mainly by stimulating the liver to produce IGF-1, which mediates most of the growth-promoting actions on bone, cartilage, and soft tissues. In adults, the long bones have already fused, so extra GH doesn’t lengthen the skeleton but leads to enlargement of tissues—hands, feet, jaw, tongue—and organs, with characteristic facial changes and potential metabolic effects like insulin resistance. The most common cause is a GH-secreting pituitary adenoma. The other hormones listed—prolactin, thyroid-stimulating hormone, and adrenocorticotropic hormone—when produced in excess cause different syndromes (for example, hyperprolactinemia, hyperthyroidism, or Cushing’s), not acromegaly.

Excess growth hormone drives acromegaly. Growth hormone exerts its effects mainly by stimulating the liver to produce IGF-1, which mediates most of the growth-promoting actions on bone, cartilage, and soft tissues. In adults, the long bones have already fused, so extra GH doesn’t lengthen the skeleton but leads to enlargement of tissues—hands, feet, jaw, tongue—and organs, with characteristic facial changes and potential metabolic effects like insulin resistance.

The most common cause is a GH-secreting pituitary adenoma. The other hormones listed—prolactin, thyroid-stimulating hormone, and adrenocorticotropic hormone—when produced in excess cause different syndromes (for example, hyperprolactinemia, hyperthyroidism, or Cushing’s), not acromegaly.