Growth-hormone-releasing hormone (GHRH) is a releasing hormone for growth hormone. It is a 44-amino acid peptide hormone produced in the arcuate nucleus of the hypothalamus. GHRH first appears in the human hypothalamus between 18 and 29 weeks of gestation, which corresponds to the start of production of growth hormone and other somatotropes in fetuses. GRF is released by the hypothalamus and acts on the adenohypophyse to stimulate the secretion of growth hormone.