What is the Origin of Melatonin Levels?

The term originates from the discovery and characterization of melatonin in the mid-20th century, a hormone derived from the amino acid tryptophan via serotonin. Its etymology is derived from its ability to affect melanophores, although its primary role in humans is neuroendocrine. The clinical focus on 'Levels' stems from the observation that nocturnal melatonin production declines significantly with age and is highly sensitive to light exposure.

What is the Mechanism of Melatonin Levels?

Melatonin functions by binding to melatonin receptors (MT1 and MT2) in the suprachiasmatic nucleus (SCN) of the hypothalamus, which is the body's central clock. This binding signals darkness, facilitating the onset of sleep and synchronizing various peripheral circadian rhythms in other tissues. Its mechanism also involves potent antioxidant and anti-inflammatory properties, contributing to cellular protection and immune modulation.

Melatonin Levels ∞ Area

Melatonin Levels

Meaning

Melatonin Levels refer to the quantifiable concentration of the hormone melatonin, primarily synthesized and secreted by the pineal gland, found in the circulation or other biological fluids like saliva and urine. These levels exhibit a distinct circadian rhythm, rising sharply in the evening to signal darkness and promote sleep, and decreasing during daylight hours. Clinically, the measurement of these levels is used to assess circadian rhythm integrity and sleep-wake cycle regulation.