Growth Hormone
Investigational
GHRP-2
Also known as: Pralmorelin, KP102, Growth Hormone Releasing Peptide 2, GHRP2, KP-102
Synthetic growth hormone releasing peptide. Studied in ghrelin-receptor and growth-hormone-axis research.
Research overview
GHRP-2 (pralmorelin, also coded KP-102) is a small synthetic peptide from the same research programme as GHRP-6, led by Cyril Bowers at Tulane University. Like GHRP-6, it acts on the growth hormone secretagogue receptor, the receptor for the hormone ghrelin. In Japan it is used as a diagnostic test, to check whether the pituitary can release growth hormone in adults suspected of growth hormone deficiency (Fukuda, 2014).
Human studies have been small and short. In six healthy young adults it raised growth hormone strongly and also caused smaller rises in prolactin, ACTH and cortisol (Arvat et al., Peptides 1997). In a study of seven healthy men, the men ate more at a buffet meal after GHRP-2 than after saline, in line with ghrelin's role in hunger (Laferrère et al., JCEM 2005). Beyond diagnostic testing there are no long-term controlled trials, and its effects over months and its long-term safety are not known. Supplied for laboratory research use only.
Mechanism of action
GHRP-2 binds the growth hormone secretagogue receptor (GHS-R1a), the receptor for the hormone ghrelin, on growth hormone producing cells in the pituitary and on nerve cells in the hypothalamus. Binding causes a short burst of growth hormone release. In human studies it also raised prolactin, ACTH and cortisol to a smaller degree, so it is not fully specific for growth hormone. Because ghrelin also signals hunger, some studies measure food intake as well as hormone levels.