Growth hormone (GH) is a protein-based poly-peptide hormone. It stimulates growth and cell reproduction and regeneration in humans and other animals. It is a 191-amino acid, single-chain polypeptide hormone that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland. Somatotropin refers to the growth hormone produced natively and naturally in animals, whereas the term somatropin refers to growth hormone produced by recombinant DNA technology,[1] and is abbreviated "rhGH" in humans.
Growth hormone is used clinically to treat children's growth disorders and adult growth hormone deficiency. In recent years, replacement therapies with human growth hormones (hGH) have become popular in the battle against aging and weight management. Reported effects on GH deficient patients (but not on healthy people) include decreased body fat, increased muscle mass, increased bone density, increased energy levels, improved skin tone and texture, increased sexual function and improved immune system function. At this time hGH is still considered a very complex hormone and many of its functions are still unknown