GHRP-2 is studied for selective agonist activity at the GHS-R1a (growth hormone secretagogue receptor 1a), which is expressed in pituitary somatotroph cells and hypothalamic nuclei. Cell-based binding assays using GHS-R1a-expressing cell lines, alongside downstream signalling readouts (such as cAMP accumulation and calcium mobilization), are standard methods for characterising GHRP-2's receptor engagement and functional potency relative to other GHS-R1a ligands.

GHRP-2 engages the ghrelin/GHS-R1a receptor pathway, distinct from the GHRH receptor pathway targeted by GHRH analogues such as CJC-1295. Research protocols frequently pair GHRP-2 with GHRH analogues to examine whether GHS-R1a agonism and GHRH receptor activation produce synergistic effects on growth hormone secretagogue signalling endpoints, a common combination design in pituitary pathway research.

Studies investigating GHRP-2 mechanisms typically incorporate vehicle controls, receptor-antagonist controls, and comparator GHS-R1a agonists to distinguish receptor-specific effects from non-specific pathway activation.

Comparative experiments using compounds such as GHRP-6 or Ipamorelin are commonly employed to evaluate differences in signalling selectivity, pathway activation patterns, receptor responsiveness, and downstream transcriptional responses. These approaches help establish mechanistic attribution in GHS-R1a pharmacology research.