Oversecretion of the pituitary hormone human growth hormone can cause gigantism if it occurs before growth of the long bones is complete, or acromegaly if it begins during adulthood. Undersecretion of human growth hormone can lead to dwarfism if experienced during childhood, and decreased endocrine function accompanied by lethargy and loss of sexual capacity in the adult.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.