RA-191AA (growth hormone (gh)) is a peptide hormone. It stimulates growth and cell reproduction in humans and other animals. It is a 191-amino acid, single chain polypeptide hormone which is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland. GH is responsible for growth and regeneration of our cells, it affects our bones, muscle, internal organs and also plays important role in countless other areas of our body.