Growth-hormone-releasing hormone 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. GHRH is released from neurosecretory nerve terminals of these arcuate neurons, and is carried by the hypothalamo-hypophyseal portal system to the anterior pituitary gland where it stimulates growth hormone (GH) secretion by stimulating the growth hormone releasing hormone receptor. GHRH is released in a pulsatile manner, stimulating similar pulsatile release of GH. In addition, GHRH also promotes slow-wave sleep directly.