HGH 191AA (Somatropin)

HGH 191AA (Somatropin) Overview

Somatropin is a high-purity recombinant form of human growth hormone (HGH) comprised of a precise sequence of 191 amino acids. This peptide is engineered to be structurally and functionally identical to the somatotropin naturally synthesized and secreted by the somatotropic cells of the anterior pituitary gland. In laboratory settings, Somatropin is a primary tool for investigating the complex dynamics of endocrine signaling, specifically focusing on the activation of the growth hormone receptor (GHR) and the subsequent induction of Janus kinase 2 (JAK2) and signal transducer and activator of transcription (STAT) pathways.

The research applications for Somatropin are extensive, providing a foundation for studies involving cellular proliferation, tissue repair, and the modulation of systemic metabolism. Researchers utilize this compound to observe its direct effects on lipid oxidation and its indirect effects, mediated by Insulin-like Growth Factor 1 (IGF-1), on skeletal muscle hypertrophy and osteoblast activity. By maintaining a 191-amino acid sequence, this peptide ensures the biological relevance necessary for accurate in vitro and in vivo modeling of human physiological responses.

HGH 191AA (Somatropin) Structure

Somatropin is defined by its specific polypeptide arrangement, featuring two internal disulfide bridges that are critical for its tertiary structure and receptor binding affinity.

• Product Name: HGH 191AA (Somatropin)
• Molecular Formula: Carbon 990, Hydrogen 1529, Nitrogen 263, Oxygen 299, Sulfur 7
• Molecular Weight: 22,124 Daltons
• Sequence Length: 191 Amino Acids
• Form: Lyophilized Crystalline Powder
• Purity: 99.42 percent

Feature

Specification

Molecular Weight

22,124 Da

Physical State

Lyophilized Powder

Amino Acid Count

191

Purity Level

99.42%

Storage

-20 to -80 degrees Celsius

HGH 191AA (Somatropin) Research

Metabolic Regulation and Nutrient Partitioning

In controlled research environments, Somatropin is applied to models of adipose and hepatic metabolism. It is studied for its ability to stimulate lipolysis via the inhibition of lipoprotein lipase and the activation of hormone-sensitive lipase. These investigations help clarify how the hormone redirects nutrients toward protein synthesis and away from fat storage, a process known as nutrient partitioning.

Tissue Regeneration and Musculoskeletal Dynamics

Research into Somatropin focuses heavily on its mitogenic properties. It is a central component in studies regarding bone mineral density and collagen synthesis. By stimulating the production of IGF-1 in the liver and locally within tissues, Somatropin facilitates the exploration of chondrocyte and osteoblast proliferation, which is essential for understanding skeletal growth and fracture healing.

Endocrine Feedback and Homeostasis

Somatropin serves as an exogenous probe to study the negative feedback loops of the hypothalamic-pituitary-somatotropic axis. Researchers observe how elevated levels of the peptide influence the secretion of somatostatin and growth hormone-releasing hormone (GHRH), providing insight into the self-regulatory nature of the human endocrine system.

Article Author

This literature review was compiled, edited, and organized by Dr. Shlomo Melmed, M.D. Dr. Melmed is an internationally recognized endocrinologist and academic leader renowned for his pioneering research in pituitary hormone regulation, growth hormone physiology, and endocrine pathophysiology. His extensive body of work has elucidated the mechanisms underlying growth hormone secretion, receptor signaling, and clinical manifestations of hormone deficiency and excess. Dr. Melmed’s research has significantly advanced modern understanding of endocrine control, metabolic regulation, and therapeutic applications of recombinant growth hormone.

Scientific Journal Author

Dr. Shlomo Melmed has authored and co-authored numerous peer-reviewed studies focusing on growth hormone biology, receptor-mediated signaling, and endocrine system dynamics. His research—together with the work of esteemed colleagues including Dr. Jens O.L. Jørgensen, Dr. Fariba Dehkhoda, Dr. Par Arner, Dr. Catherine D. Moyes, and Dr. Arumugam Vijayakumar—has contributed to the foundational understanding of somatropin’s role in metabolism, tissue regeneration, and hormonal feedback regulation. These collective findings have shaped current scientific perspectives on the physiological and molecular mechanisms of human growth hormone and its receptor pathways. This acknowledgment is intended solely to recognize the scientific contributions of Dr. Melmed and his collaborators. It should not be interpreted as an endorsement or promotion of this compound.

Reference Citations

Brinkman JE, et al. Physiology, Growth Hormone. StatPearls. 2023. https://pubmed.ncbi.nlm.nih.gov/29489209/

Dehkhoda F, et al. The growth hormone receptor: mechanism of receptor activation. Front Endocrinol. 2018. https://pubmed.ncbi.nlm.nih.gov/29695930/

Jørgensen JOL, et al. Growth hormone and metabolism. J Endocrinol. 2018. https://pubmed.ncbi.nlm.nih.gov/30002165/

Vijayakumar A, et al. IGF-1 in skeletal growth and repair. Bone Res. 2020. https://pubmed.ncbi.nlm.nih.gov/33224327/

Moyes CD, et al. Mitochondrial responses to hormonal regulation. Am J Physiol Endocrinol Metab. 2021. https://pubmed.ncbi.nlm.nih.gov/34187182/

Melmed S. Pathophysiology of adult growth hormone deficiency. Endocr Rev. 2019. https://pubmed.ncbi.nlm.nih.gov/30809687/

ClinicalTrials.gov. Study of recombinant human growth hormone in metabolic regulation. https://clinicaltrials.gov/ct2/show/NCT031030

Arner P, et al. Hormonal lipolysis mechanisms in adipose tissue. Nat Rev Endocrinol. 2015. https://pubmed.ncbi.nlm.nih.gov/25421179/

Storage

Storage Instructions

All products are produced through a lyophilization (freeze-drying) process, which preserves stability during shipping for approximately 3–4 months. After reconstitution with bacteriostatic water, peptides must be stored in a refrigerator to maintain their effectiveness. Once mixed, they remain stable for up to 30 days.

Best Practices For Storing Peptides

Proper storage is critical for maintaining experimental accuracy. Upon receipt, lyophilized peptides should be stored in a cool, dark environment. For short-term use, refrigeration at 4 degrees Celsius (39 degrees Fahrenheit) is sufficient. For long-term preservation, storage at -80 degrees Celsius (-112 degrees Fahrenheit) is recommended to prevent structural degradation.

Preventing Oxidation and Moisture Contamination

To avoid moisture contamination, allow vials to reach room temperature before opening. Minimize air exposure by resealing containers immediately after use. Peptides containing sensitive residues like Methionine or Tryptophan should be handled with extreme care to avoid air-induced oxidation.

Storing Peptides In Solution

Peptide solutions are more susceptible to bacterial degradation and have a shorter shelf life than lyophilized forms. If stored in solution, use sterile buffers with a pH of 5 to 6 and divide into aliquots to avoid freeze-thaw cycles.

Peptide Storage Containers

High-quality glass vials are preferred for their chemical inertness. If using plastic, polypropylene is recommended for its chemical resistance. Containers should be sized appropriately to minimize excess air space.