HGH 191AA (Somatropin)

Description

HGH 191AA (also Somatropin) is a recombinant form of human growth hormone with the complete 191-amino acid sequence identical to the endogenously produced variant from the pituitary. Manufactured via recombinant DNA technology, the substance serves as a research reference compound for studies on GH receptor activation, signal transduction and endocrine pathways.

Per study reports, HGH 191AA is used in a wide variety of study designs: investigations of growth hormone receptor binding, JAK2/STAT5 signal transduction, protein synthesis pathways, the IGF-1 axis and metabolic adaptation. Due to the precise sequence match with the natural hormone, the compound also serves as a reference standard in bioassays and immunoassays.

In preclinical research settings, effects on cell proliferation, lipid metabolism, muscle physiology, bone density and regenerative pathways are investigated. Action occurs through binding to growth hormone receptors (GHR) on target cells, followed by activation of Janus kinases and downstream transcription factors. IGF-1 is considered the central downstream mediator.

HGH 191AA is delivered lyophilized and differs pharmacologically from secretagogues such as CJC-1295 or Ipamorelin: while secretagogues stimulate the endogenous GH axis, here the substance is directly administered. This has consequences in research setups for natural pulsatility and HPA axis regulation.

You can order HGH 191AA in 10-vial packs at 36iu per vial.

This information is for research and educational purposes only. No medical recommendations.

Risks & Safety

HGH 191AA is considered well characterized and largely well tolerated per study reports. Unlike GH secretagogues, here the hormone is directly administered, which makes the effects more pronounced and less tied to the natural feedback loop.

Observed in research and user reports:

• Injection site: mild redness, pressure or transient irritation at the injection site is the most common observation with subcutaneous use.
• GH-typical effects: as is common with direct GH administration, the literature describes water retention as well as numbness or tingling in the hands (carpal-tunnel-type symptoms) and joint discomfort, usually dose-dependent.
• Glucose metabolism: elevated GH levels can raise fasting blood glucose and reduce insulin sensitivity in studies - tending to be more pronounced with direct administration than with secretagogues.
• Loss of pulsatility: direct substance administration bypasses the natural pulsatile GH secretion and can modulate endogenous axis regulation.
• No long-term data: robust long-term human studies on research use do not exist. The profile rests primarily on short-term studies and anecdotal experience.

This classification does not replace medical advice. Risk and responsibility for any actual use lie entirely with the buyer.

Studies

• Recombinant human growth hormone and its effects on cell proliferation - Endocrine Reviews 2001: Review on GH and cell proliferation in research models.
• Somatropin and its role in metabolic and regenerative research - Journal of Clinical Endocrinology & Metabolism 2004: Research review on metabolic regulation.
• GH-mediated JAK2/STAT5 signaling in tissue regeneration studies - Molecular Endocrinology 2010: Mechanism study on the signaling pathway.
• Somatropin and its applications in musculoskeletal research - Frontiers in Endocrinology 2017: Current review on application research.