Sermorelin is a synthetic 28-amino acid peptide analog of growth hormone-releasing hormone (GHRH). Sermorelin exhibits immunomodulatory and pro-angiogenic activities. In vivo, sermorelin stimulates secretion of growth hormone from the pituitary gland; it also increases IGF-1 secretion and increases the number of activated immune cells in circulation. Sermorelin induces histamine release from mast cells in a Ca2+-dependent manner. Additionally, this peptide increases secretion of VEGF and chromogranin A, increasing proliferation in neuroendocrine tumor cells.