By the Banger Labs Research Team · Updated June 2026
What is HGH 191AA?
Somatropin is a recombinant form of the dominant 191-amino-acid isoform of human growth hormone (approximately 22 kDa), produced by recombinant expression in bacterial or mammalian cell systems. Structurally it adopts a characteristic four-helix-bundle topology stabilized by two intramolecular disulfide bonds, and it belongs to the somatotropin/cytokine-family polypeptide hormone class. In a research setting it is handled as a reference polypeptide for studying growth-hormone biology.
How HGH 191AA is studied
In published mechanistic studies, growth hormone binds the growth hormone receptor (GHR), a member of the class I cytokine receptor superfamily, with one hormone molecule engaging two receptor subunits and inducing a conformational change in pre-formed receptor dimers. This activates the receptor-associated JAK2 tyrosine kinase, which phosphorylates the receptor and STAT proteins (notably STAT5B), driving transcription of target genes. A central downstream node reported in the literature is stimulation of insulin-like growth factor-1 (IGF-1) production, predominantly in the liver; the MAPK and PI3K pathways are also reported as activated.
Research areas
- Studied as a reference ligand in growth-hormone receptor (GHR) binding and dimerization research models
- Investigated in JAK2/STAT5B intracellular signal-transduction research
- Used in preclinical and in vitro studies of the GH-IGF-1 endocrine axis
- Examined in research on GH-mediated gene regulation and downstream MAPK/PI3K pathway activation
- Serves as a recombinant-protein reference standard for somatotropin structure-function laboratory research
These describe laboratory/preclinical research only. No therapeutic, medical, or efficacy claims are made.
HGH 191AA specifications
Handling & quality
HGH 191AA is held to a ≥ 99% HPLC purity standard with a Certificate of Analysis available per batch. Reconstitute with bacteriostatic water and store refrigerated; handle strictly for research. See reconstitution & storage.
Frequently asked questions
What is HGH 191AA?
Somatropin is a recombinant form of the dominant 191-amino-acid isoform of human growth hormone (approximately 22 kDa), produced by recombinant expression in bacterial or mammalian cell systems. Structurally it adopts a characteristic four-helix-bundle topology stabilized by two intramolecular disulfide bonds, and it belongs to the somatotropin/cytokine-family polypeptide hormone class. In a research setting it is handled as a reference polypeptide for studying growth-hormone biology.
Is HGH 191AA research use only?
Yes. HGH 191AA is supplied strictly for laboratory research — not for human or veterinary use, and not as a drug, food, or supplement.
Does Banger Labs provide a COA for HGH 191AA?
Yes — a Certificate of Analysis (HPLC purity + mass-spec identity) is available per batch on request. See the COA Library.
References
- The Growth Hormone Receptor: Mechanism of Receptor Activation, Cell Signaling, and Physiological Aspects — Frontiers in Endocrinology, 2018 (PMC)
- Growth hormone signaling pathways — Growth Hormone & IGF Research, 2015 (PMC)
- Human Growth Disorders Associated with Impaired GH action: Defects in STAT5B and JAK2 — Molecular and Cellular Endocrinology, 2020 (PMC)
- Growth hormone — Wikipedia (overview/structure reference)
Sources are provided for scientific reference and describe laboratory/preclinical research; they do not constitute medical advice or efficacy claims.
Shop HGH 191AA & related research peptides
By the Banger Labs Research Team. For research use only. Not for human or veterinary use. Not a drug, food, or cosmetic. Educational information, not medical advice.