GHRP-6

GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide that acts as a potent growth hormone secretagogue by activating the ghrelin receptor (GHS-R1a). Developed in the 1980s, it was one of the first synthetic GH secretagogues identified and has been extensively studied in both preclinical and clinical settings.

GHRP-6 stimulates GH release through a dual mechanism: direct action on pituitary somatotrophs via the ghrelin receptor and indirect amplification through hypothalamic GHRH neurons. A notable characteristic of GHRP-6 is its strong appetite-stimulating effect, mediated through the same ghrelin receptor pathway. It also transiently elevates cortisol and prolactin levels, which distinguishes it from more selective secretagogues like Ipamorelin.

Research has demonstrated that GHRP-6 produces robust, dose-dependent GH release with peak levels occurring approximately 15-30 minutes after administration. Studies have explored its applications in muscle wasting, growth hormone deficiency, and cardiac protection. Animal research has shown cardioprotective properties, including reduced infarct size and improved cardiac function following ischemia-reperfusion injury.