HGH 191AA (Somatropin)

HGH 191AA (Somatropin)

Somatropin is a recombinant form of human growth hormone, a polypeptide composed of 191 amino acids. It is structurally and biologically identical to the hormone naturally secreted by the pituitary gland. In controlled laboratory environments, it is studied for its effects on cellular growth, protein synthesis, and metabolic regulation, acting primarily through activation of its specific growth hormone receptors and downstream IGF-1–mediated signaling pathways.

HGH 191AA (Somatropin) Overview

Somatropin is a valuable tool in diverse research areas, including growth hormone deficiency modeling, metabolic regulation, and cellular regeneration processes. In experimental systems, it is utilized to investigate the molecular and physiological mechanisms underlying tissue maintenance, energy utilization, and adaptive remodeling. Research studies frequently employ somatropin to examine its influence on skeletal muscle hypertrophy, bone density, lipid mobilization, and nutrient partitioning. These analyses provide insights into how growth hormone signaling influences anabolic processes, mitochondrial bioenergetics, and overall metabolic homeostasis.

HGH 191AA (Somatropin) Structure

Chemical Makeup

• Somatropin is a single-chain polypeptide hormone.
• Amino Acid Count: 191 amino acids.
• Structural Identity: Identical to pituitary-derived human growth hormone.
• Observed Mass: Approximately 22,124 Da.

HGH 191AA (Somatropin) Research

Somatropin in Metabolic Regulation Models

In controlled metabolic research models, somatropin is utilized to investigate its influence on lipid mobilization, carbohydrate turnover, and energy equilibrium. Studies focus on how somatropin modulates nutrient utilization, substrate oxidation, and overall metabolic rate through its interaction with growth hormone and insulin-like growth factor (IGF) pathways.

Somatropin in Growth and Regeneration Research

Research involving somatropin examines its role in promoting bone mineralization, collagen synthesis, and cellular regeneration associated with tissue repair and developmental biology. Experimental investigations highlight somatropin’s contribution to musculoskeletal remodeling, connective tissue maintenance, and wound healing through anabolic and mitogenic signaling cascades, including those related to cell proliferation.

Somatropin and Endocrine System Feedback

Laboratory experiments employ somatropin to study endocrine feedback mechanisms and its interactions with intrinsic regulatory hormones. These models explore the effects of somatropin on hypothalamic-pituitary communication, feedback inhibition, and adaptive hormonal modulation within endocrine networks.

This compound is intended strictly for controlled scientific research by qualified professionals. It is not approved for human or veterinary use.

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. The author and affiliated organizations have no professional, commercial, or research relationship with any manufacturers or distributors of HGH (Somatropin).

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.g ov/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 manufactured via a lyophilization (freeze-drying) process, ensuring stability during shipping for approximately 3–4 months. After reconstitution with bacteriostatic water, peptides must be stored in a refrigerator to maintain efficacy, remaining stable for up to 30 days once mixed. Lyophilization, or cryodesiccation, is a specialized dehydration method where peptides are frozen and exposed to low pressure, causing water to sublimate directly from solid to gas. This leaves behind a stable, white crystalline powder that can be safely kept at room temperature until reconstitution. For long-term storage (several months to years), freezing at -80°C (-112°F) is recommended to maintain the peptide’s structural integrity and ensure stability.

Best Practices For Storing Peptides

Proper storage is critical to maintaining the accuracy and reliability of laboratory results by preventing contamination, oxidation, and degradation.

• Lyophilized Storage: For long-term preservation, peptides should be stored in a freezer at -80°C (-112°F). For short-term use, refrigeration below 4°C (39°F) is adequate.
• Handling: Minimize freeze-thaw cycles to prevent degradation. Avoid frost-free freezers due to temperature variations during defrosting cycles.

Preventing Oxidation and Moisture Contamination

Peptides must be protected from air and moisture exposure, which compromise stability.

• Condensation Control: Always allow the cold vial to reach room temperature before opening to prevent condensation from contaminating the peptide.
• Air Exposure: Minimize air exposure by promptly resealing the container after removing the required amount.
• Aliquot: To preserve long-term stability and prevent repeated air exposure, divide the total peptide quantity into smaller aliquots for individual experimental use.

Storing Peptides In Solution

Peptide solutions have a significantly shorter shelf life and are more susceptible to degradation than lyophilized forms.

• Reconstituted Stability: Under refrigerated conditions at 4°C (39°F), most peptide solutions remain stable for up to 30 days.
• Buffer/pH: If solution storage is necessary, use sterile buffers with a pH between 5 and 6.
• Aliquot and Freeze: Divide the solution into aliquots to minimize freeze-thaw cycles. Unstable peptides should be frozen when not in immediate use.

Peptide Storage Containers

High-quality glass vials offer optimal characteristics (clarity, stability, chemical inertness). Containers should be sized appropriately to minimize excess air space.