
Research peptides that probe the somatotropic axis. The category groups GHRH analogs such as Tesamorelin and Sermorelin, which drive pulsatile endogenous GH release; GHRPs such as Ipamorelin, Hexarelin, GHRP-2 and GHRP-6, which act at the ghrelin receptor; GH fragments such as HGH Fragment 176-191 and AOD-9604, which model lipolytic activity without raising IGF-1; and HGH 191AA (somatropin), the full 191-amino-acid recombinant sequence that covers the entire GH axis including anabolic and IGF-1-mediated effects.
Growth Hormone Peptides groups four agent classes of the somatotropic axis: GHRH analogs, GHRPs, GH fragments, and full-length somatropin. Every product is HPLC-tested, labelled Research Use Only, and intended exclusively for in-vitro and preclinical research.
GHRH analog, GHRP, GH fragment, and full-length somatropin are often run in separate experimental arms to cleanly separate pulsatile GH release, synergistic secretagogue effects, direct lipolysis, and anabolic IGF-1-mediated effects.
Tesamorelin is a synthetic GHRH analog with an additional trans-3-hexenoyl group at the N-terminus that improves enzymatic stability. Research groups use it to study the pulsatile release of endogenous growth hormone and the downstream IGF-1 response. Typical study areas include visceral adipose tissue and HIV-associated lipodystrophy (Falutz et al., NEJM 2007; Stanley et al., JCEM 2019). Its plasma half-life is approximately 30 minutes, but the biological window is longer because the triggered GH pulse itself unfolds on a delayed timescale.
Growth Hormone groups research peptides that engage the somatotropic axis, the hormonal cascade that links the hypothalamus, the pituitary, and peripheral target tissues. GHRH analogs such as Tesamorelin and Sermorelin mimic hypothalamic growth-hormone-releasing hormone and stimulate pulsatile endogenous GH release from the pituitary, followed by a consecutive IGF-1 response. GHRPs such as Ipamorelin, Hexarelin, GHRP-2 and GHRP-6 act through the ghrelin receptor (GHS-R) and trigger GH secretion via a second, complementary pathway. GH fragments such as HGH Fragment 176-191 and AOD-9604 correspond to the C-terminal segment of human growth hormone and are studied for lipolytic mechanisms that operate independently of the IGF-1 pathway. HGH 191AA (somatropin) reproduces the complete 191-amino-acid sequence and engages the entire GH axis, driving JAK2/STAT5 signaling, hepatic IGF-1 induction, and peripheral lipolysis in one molecule. The category is built for preclinical work on GH pulsatility, fat metabolism, visceral-adipose models, protein synthesis, bone and muscle turnover, and interactions with other metabolic peptides in controlled experimental settings.
The four classes act at different points of the somatotropic axis and are therefore deliberately separated or combined in research. The overview below maps the peptides in this category to their points of action and typical research endpoints:
The peptides in this category are characterized against clearly defined endpoints. At the axis level, pulsatile GH release is central: GHRH analogs and GHRPs trigger secretagogue-mediated pulses whose amplitude and frequency are quantified in pituitary and animal models. Downstream follows the IGF-1 response, which serves as a marker of somatotropic activity and is measurable especially in hepatocytes. At the molecular level, full-length somatropin activates the JAK2/STAT5 cascade after receptor dimerization; STAT5 phosphorylation and hepatic IGF-1 mRNA expression are established readouts. The lipolytic component is modelled through GH fragments: AOD-9604 and HGH Fragment 176-191 increase fat oxidation and lipolysis in the adipocyte in preclinical models without meaningfully activating the IGF-1 pathway, which allows a clean separation of the anabolic and metabolic axes. Further typical endpoints include markers of bone and muscle turnover as well as counter-insulinic effects in animal models.
Every peptide is tested by HPLC for purity of at least 99% and confirmed by mass spectrometry for identity and molecular weight. Certificates of Analysis (CoAs) are available on request and document the respective batch. All products are labelled Research Use Only (RUO) and intended exclusively for in-vitro experiments and preclinical research; they are not approved for human or veterinary use and do not follow a pharmaceutical quality regime. Sequence and molecular-weight data are listed on the product pages, so that weighing and working concentration can be calculated precisely for each individual protocol in the receiving laboratory.
Lyophilized peptides are stable at −20 °C for 24 months and should be kept dry and protected from light until reconstitution. For experiments, reconstitution is typically performed with bacteriostatic water; the resulting solution remains usable at 2 to 8 °C for 28 days. Working concentrations follow the respective study protocol and the vial size in use. Aliquot stock solutions early to minimize freeze-thaw cycles and store them protected from light. Avoid vigorous shaking against the vial wall and allow the lyophilizate to equilibrate to room temperature before use to protect peptide integrity.