Amino acid sequence: D-Ala-D-β-Nal-Ala-Trp-D-Phe-Lys-NH2 Formula: C45H55N9O6 Mol. Mass: 817.9 g/mol Half-life: Between 15 and 60 minutes
Sterile Filtered White lyophilized (freeze-dried) powder. Growth hormone releasing peptide (GHRP-2) is the most potent of the GH secretagogues.
Growth hormone secretagogues stimulate the anterior pituitary gland causing an increase in GH release. This was demonstrated in an early study, GHRP-2 (also known as KP-102) was tested on adult male rats: KP-102 induced a large plasma GH response at a dose of 0.5 micrograms/kg BW in conscious rats, although GH-releasing abilities of KP-102 varied markedly depending on the phase of GH secretion.
It produced a large plasma GH response in the presence of exogenous GH-releasing factor (GRF). During intermittent administration of GRF, the somatotropes became refractory to a large bolus dose of GRF, but KP-102 induced a marked increase of plasma GH. KP-102 and GRF acted synergistically on GH secretion in control animals.
Taken together, these findings suggest that the KP-102-induced GH secretion largely depends on GRF and the secretagogue potentiates the GRF effect by antagonizing the SS action at the level of somatotropes.