CAS Number: 21898-19-1
Molecular Formula: C₁₂H₁₈Cl₂N₂O
Molecular Weight: 277.19 g/mol
Synonyms: Spiropent, Ventipulmin, Clenbuterol HCl
Abstract
Clenbuterol Hydrochloride is a β₂-adrenergic receptor agonist extensively researched for its impact on lipid metabolism, energy expenditure, thermogenesis, and muscle physiology in animal and in vitro studies.
Through its selective interaction with β₂-adrenoceptors, Clenbuterol stimulates cyclic AMP (cAMP) signaling, enhancing fat oxidation and mitochondrial activity.
This compound has become an important model in metabolic and adrenergic research — particularly in understanding skeletal muscle hypertrophy, lipolysis, and bronchial relaxation mechanisms in controlled scientific environments.
⚠️ Regulatory Disclaimer:
Clenbuterol Hydrochloride is not approved by the U.S. FDA for human or veterinary use.
This compound is sold strictly for laboratory research purposes only.
Chemical Properties
| Property | Specification |
|---|---|
| Chemical Name | Clenbuterol Hydrochloride |
| CAS Number | 21898-19-1 |
| Molecular Formula | C₁₂H₁₈Cl₂N₂O |
| Molecular Weight | 277.19 g/mol |
| Purity | ≥98% (HPLC) |
| Appearance | White crystalline powder |
| Solubility | Soluble in water |
| Storage | Store at –20°C, protected from light and moisture |
| Stability | Stable for 24 months when stored properly |
Introduction
Clenbuterol Hydrochloride is a synthetic sympathomimetic amine that selectively targets β₂-adrenergic receptors.
It was originally developed as a bronchodilator but is now primarily used as a research compound for studying adrenergic pathways and metabolic effects.
Research models have demonstrated its ability to:
- Increase thermogenesis and energy expenditure
- Enhance fatty acid oxidation
- Preserve lean muscle mass under catabolic conditions
- Stimulate mitochondrial biogenesis
Because of these effects, Clenbuterol is a common subject of study in metabolic disease models, respiratory research, and skeletal muscle physiology.
Mechanism of Action
Clenbuterol acts by binding to β₂-adrenergic receptors, leading to activation of adenylate cyclase and increased cyclic AMP (cAMP).
This triggers protein kinase A (PKA) activation, resulting in phosphorylation of downstream enzymes that regulate lipid metabolism, glycogenolysis, and thermogenic activity.
Key preclinical findings:
- Lipolytic activity through activation of hormone-sensitive lipase.
- Thermogenic upregulation via uncoupling protein stimulation.
- Anabolic-like effects in skeletal muscle by enhancing protein synthesis in animal models.
Preclinical Studies (PubMed References)
- Revisiting the pharmacological properties of Clenbuterol.
Pharmacol Res. 2009;60(6):475-482.
PubMed: 19695354 - β2-Adrenoceptor agonist-induced hypertrophy in skeletal muscle.
Am J Physiol. 1995;268(6):E1070–E1076.
PubMed: 7611396 - Effects of Clenbuterol on lipid metabolism in rats.
Br J Pharmacol. 1987;91(4):803–814.
PubMed: 2893172 - Adrenergic regulation of skeletal muscle metabolism by β2-agonists.
Muscle Nerve. 1998;21(9):1290–1296.
PubMed: 9703451 - Adrenergic receptor signaling in energy regulation and mitochondrial efficiency.
Endocrinology. 2001;142(3):1070–1076.
PubMed: 11181597
Research Applications
- Metabolic Research: Investigating thermogenic pathways, lipolysis, and energy regulation.
- Skeletal Muscle Studies: Understanding hypertrophy and anti-catabolic effects in animal models.
- Mitochondrial Function: Evaluating Clenbuterol’s role in oxidative metabolism and mitochondrial biogenesis.
- Respiratory Studies: Examining β₂-agonist mechanisms in smooth muscle relaxation and airway dilation.
These applications are for scientific and in vitro research only.
Safety and Compliance
- Use: For laboratory research purposes only.
- Not approved for: Human or veterinary use.
- Storage Conditions: Store in a cool, dark, dry environment (–20°C).
- Handling: Use laboratory-grade PPE (gloves, goggles, lab coat).
This compound is provided in accordance with FDA and DEA research regulations.
Conclusion
Clenbuterol Hydrochloride (CAS 21898-19-1) is a potent β₂-adrenergic agonist and valuable model for studying energy metabolism, thermogenesis, and adrenergic signaling.
In laboratory environments, Clenbuterol continues to serve as a benchmark compound for understanding the biological mechanisms underlying fat oxidation, muscle growth, and respiratory regulation.
All research utilizing Clenbuterol should adhere strictly to non-human, in vitro, or animal-only study protocols in compliance with U.S. research chemical standards.
SEO Keywords
Primary Keywords:Clenbuterol Hydrochloride CAS 21898-19-1, Clenbuterol research chemical, β2 adrenergic receptor agonist, Clenbuterol metabolic research, Clenbuterol laboratory compound
Secondary Keywords:Clenbuterol thermogenic peptide, Clenbuterol research study, adrenergic receptor signaling, Clenbuterol fat metabolism, scientific research compound
10 Frequently Asked Questions (Research Context)
1. What is Clenbuterol Hydrochloride?
Clenbuterol Hydrochloride is a β₂-adrenergic receptor agonist used for laboratory studies on metabolism, lipolysis, and muscle regulation.
2. What is the CAS number for Clenbuterol?
The CAS number is 21898-19-1.
3. Is Clenbuterol approved for human use?
No. It is not approved by the FDA and is for research use only.
4. What are the primary research applications?
Clenbuterol is studied for thermogenesis, fat oxidation, skeletal muscle preservation, and adrenergic receptor signaling.
5. How does Clenbuterol work?
It activates β₂-adrenergic receptors, increasing cAMP and stimulating metabolic and thermogenic pathways.
6. Can Clenbuterol be used in humans or animals?
No. It is not for human or veterinary consumption and may only be used in controlled laboratory environments.
7. How should Clenbuterol be stored?
Store below –20°C, protected from light and humidity.
8. What safety measures should be followed?
Always use gloves, lab coat, and protective eyewear; handle in a certified laboratory.
9. What is the purity specification for Clenbuterol research grade?
Typically ≥98% purity, verified via HPLC testing.
10. Where can I find supporting research on Clenbuterol?
Refer to studies listed in PubMed, including:
✅ Summary:
Clenbuterol Hydrochloride (CAS 21898-19-1) is a research-grade β₂-adrenergic receptor agonist used in metabolic, muscle, and respiratory research.
Supplied strictly for scientific investigation, it offers insight into lipid metabolism, thermogenesis, and adrenergic function — not for human use
