HGH 191AA (Somatropin)

HGH 191AA (Somatropin) research grade, multiple IU sizes available. Sourced from verified Chinese manufacturer. HPLC-verified, purity tested per batch.

HGH 191AA (somatropin) is the reference growth hormone in china peptide catalogs and one of the most expensive per-vial listings, which is why documentation discipline matters most here. Counterfeit and under-filled somatropin vials circulate widely in the chinese peptides trade. Every vial we supply carries the manufacturer’s specification and lot record — the standard the category should have had from the start.

Buy HGH 191AA (Somatropin) | Research Grade | Direct from China | Peptides of China HGH 191AA (Somatropin) Buy HGH 191AA (Somatropin) — Research Grade HGH 191AA (Somatropin) is a muscle & performance research compound currently in stock directly from a verified Chinese manufacturer. Every batch is tested by the manufacturer for purity and concentration as part of routine quality control. Sourcing is direct — no intermediaries. Public catalog minimum is $300 in goods per supplier. Eligible new customers may use one first-order trial without a monetary minimum; 5% off goods applies from $3,500 per supplier, excluding shipping. International shipping available.

Compound Profile

HGH 191AA refers to recombinant human growth hormone (rhGH), also known as somatropin — a 191-amino acid single-chain protein that is the authentic sequence and structural equivalent of endogenous pituitary-derived growth hormone. The ‘191AA’ designation reflects the complete 22 kDa isoform, which is the predominant circulating form of GH (approximately 75% of pituitary GH secretion). Recombinant somatropin is produced by heterologous expression in E. coli or mammalian cell systems using recombinant DNA technology, and the resulting protein — after purification and refolding — is structurally identical to native pituitary GH, including its two disulfide bonds (Cys-53/165 and Cys-182/189) and its tertiary four-helix bundle conformation. This structural fidelity is critical for full GH receptor (GHR) binding and activation. GH’s biological effects are mediated through two sequential pathways: direct GH receptor (GHR) activation producing acute metabolic effects (lipolysis, antagonism of insulin action, amino acid uptake in muscle), and indirect IGF-1-mediated anabolic effects (protein synthesis, cell proliferation, linear bone growth) via hepatic and local IGF-1 production. Research with recombinant GH (somatropin) is used to characterise both pathways across tissues, to establish reference pharmacokinetic and pharmacodynamic benchmarks for newer GH secretagogue compounds (sermorelin, tesamorelin, ipamorelin, CJC-1295), and to study GH receptor downstream signalling (JAK2/STAT5 pathway) in target cells. rhGH serves as the positive control in comparative studies of GH axis peptides. Peptides of China supplies HGH 191AA (somatropin) as lyophilized powder at ≥98% purity, verified by HPLC and confirmed by mass spectrometry. Certificates of Analysis available per batch. Wholesale quantities on request. For laboratory research use only.

Profile

Available Variants

Specification Highlights

Research Areas

GH Receptor Signalling & JAK2/STAT5 Research GHR activation by somatropin recruits and activates JAK2 (Janus kinase 2), which phosphorylates STAT5a/b (Signal Transducer and Activator of Transcription 5). Phospho-STAT5 dimers translocate to the nucleus and drive transcription of IGF-1, acid labile subunit (ALS), and SOCS (Suppressors of Cytokine Signalling) genes. GHR-transfected cell lines (IM-9, 3T3-F442A) and primary hepatocytes are used to characterise JAK2/STAT5 phosphorylation kinetics, receptor internalisation, and SOCS feedback by Western blotting, phosphoproteomics, and STAT5 reporter assays. Somatropin is the reference agonist in all such studies. Body Composition & Metabolic Research Somatropin’s dual metabolic role — direct lipolysis (via HSL activation in adipocytes) and indirect anabolic action (via IGF-1 in muscle and bone) — is characterised in rodent models of GH deficiency (hypophysectomised rats, lit/lit mice, dwarf rats) and in diet-induced obesity models. Body composition endpoints (lean mass, fat mass by DEXA or MRI) and metabolic endpoints (RQ, fatty acid oxidation, glucose turnover by isotope dilution) are used to quantify GH-mediated metabolic shifts. These preclinical datasets provide the reference pharmacodynamics against which GH secretagogue compounds (ipamorelin, tesamorelin, CJC-1295) are benchmarked. Linear Bone Growth & IGF-1 Axis GH and IGF-1 are the principal regulators of longitudinal bone growth at the growth plate (epiphyseal cartilage). In hypophysectomised rat growth plate models, somatropin restores chondrocyte proliferation (measured by BrdU incorporation), collagen II and X expression, and tibial growth plate width in a dose-dependent manner. IGF-1 ELISA in serum and liver provides the downstream hormonal endpoint. Local versus systemic GH effects are dissected using liver-specific IGF-1 knockout (LI-IGF-1-/-) mice, which distinguish hepatic IGF-1 from autocrine/paracrine IGF-1 production in skeletal tissue. Reference Standard for GH Secretagogue Studies All preclinical and clinical evaluation of GH secretagogue peptides (GHRH analogues, GHRPs) uses exogenous somatropin as the positive control benchmark for GH-axis pharmacological effects. Comparative studies examine whether secretagogue-stimulated endogenous GH release produces equivalent downstream effects (IGF-1, IGFBP-3, bone markers, lean mass changes) at equivalent GH exposure levels as direct somatropin administration. This dose-equivalence methodology requires precise somatropin dose-response characterisation in each model system, making high-purity research-grade somatropin essential. ## Sourcing HGH 191AA (Somatropin) From China

HGH 191AA (Somatropin) is available through our platform as a china peptide sourced directly from an established Chinese manufacturer. Three points define how we handle it:

• Factory-direct, not trader-sourced. We confirm availability and specification with the manufacturer before the order is confirmed. There is no intermediary resale of unknown-origin vials in this catalog.
• Specification before shipment. The purity and concentration specification shown on this page is the manufacturer’s batch specification. Product-specific quality-control information travels with the order.
• Research-use discipline. Like every listing in our catalog, HGH 191AA (Somatropin) is supplied for laboratory research use only, under strict research-use terms.

For buyers comparing chinese peptides suppliers, the practical test is whether the seller can name the manufacturer and show the batch documentation. We work the other way around: the manufacturer and the documentation are the offer. Browse the full catalog or see how sourcing works.