Sermorelin is a GHRH (growth hormone–releasing hormone) peptide analogue. Its peptide sequence is comprised of 29 amino acids. This sequence is a portion of the endogenous human GHRH, and is currently considered to be the shortest synthetic peptide that possesses the full array of functional GHRH activity. Due to this fact, sermorelin is considered to be a growth hormone secretagogue.
Sermorelin has been used during research to stimulate the secretion of growth hormone from the adenohypophysis (also called the anterior pituitary). The anterior pituitary secretes trophic hormones. Sermorelin has also been used in research stimulation tests to assess for pituitary sufficiency in relation to the secretion of the growth hormone.
Growth hormone–releasing hormone
GHRH is 44 amino-acids polypeptide that stimulates the secretion of growth hormone from the adenohypophysis. It is also called somatocrinin or somatoliberin. It is produced in the cell bodies of periventricular arcuate neurons, and thereafter transported to the neurosecretory terminals of the neurons where they are released. The arcuate neurons do form part of the hypothalamo-hypophyseal portal system. Their release from the neurosecretory terminals occur in a pulsatile fashion and it thus follows that growth hormone (GH) release also occurs in a corresponding pulsatile fashion. GHRH binds to a secretin-type G-protein coupled serpentine receptor called the GHRH-receptor (GHRHR).