Melatonin

Melatonin

Melatonin (N-acetyl-5-methoxytryptamine) is an endogenous indoleamine neurohormone synthesised primarily in the pineal gland from serotonin via sequential acetylation and methylation. It is the principal hormonal signal of circadian darkness, secreted nocturnally in response to light-dark cycle information relayed from the suprachiasmatic nucleus (SCN). Melatonin is one of the most extensively studied chronobiological molecules, with well-characterised roles in circadian rhythm entrainment, sleep regulation, antioxidant defence, immune modulation, and oncostatic signalling. It is supplied here as a research-grade compound for in vitro and preclinical investigation.

Mechanism of Action

Melatonin acts primarily through two high-affinity G-protein-coupled receptors, MT1 (MTNR1A) and MT2 (MTNR1B), expressed in the SCN, retina, peripheral tissues, and immune cells. MT1 activation inhibits neuronal firing in the SCN via Gi-mediated cAMP suppression, promoting sleep onset and phase-shifting circadian rhythms. MT2 activation modulates phase-shifting responses and retinal dopamine release. Beyond receptor-mediated signalling, melatonin is a potent direct free radical scavenger and indirect antioxidant, upregulating superoxide dismutase, catalase, and glutathione peroxidase. It also modulates NF-κB signalling, cytokine production, and natural killer cell activity, supporting its investigation in neuroimmune and oncology research.

Research Applications

• MT1/MT2 receptor pharmacology and circadian rhythm regulation studies
• Sleep-wake cycle, chronobiology, and SCN function research
• Antioxidant defence, free radical scavenging, and oxidative stress investigation
• Neuroimmune modulation and cytokine regulation research
• Oncostatic signalling and cancer biology preclinical models

Specifications

• Molecular Formula: C₁₃H₁₆N₂O₂
• Molecular Weight: 232.3 g/mol
• CAS Number: 73-31-4
• Purity: ≥98%
• Form: Lyophilised powder
• Storage: -20°C
• Shelf Life: 24 months

This product is intended for legitimate laboratory and analytical research use only. Not for diagnostic, therapeutic, or consumer use.