What is the Origin of Melatonin Cascade?

This term is derived from chronobiology and endocrinology, referencing the biochemical pathway that transforms serotonin into melatonin. The 'cascade' metaphor aptly describes the sequential enzymatic reactions and subsequent systemic hormonal signaling that follows environmental light detection.

What is the Mechanism of Melatonin Cascade?

The process begins when reduced photonic input signals the SCN to disinhibit the sympathetic outflow to the pineal gland. This leads to the upregulation of AANAT (arylalkylamine N-acetyltransferase), the rate-limiting enzyme in melatonin synthesis from serotonin. The resulting nocturnal rise in circulating melatonin then acts on MT1 and MT2 receptors throughout the body to promote sleep propensity and modulate the timing of other hormone releases.

Melatonin Cascade

Meaning

The Melatonin Cascade describes the sequence of neuroendocrine events initiated by darkness, leading to the synthesis and rhythmic release of the hormone melatonin from the pineal gland. This cascade functions as a critical signaling mechanism, informing the body about the time of day and initiating processes related to rest, repair, and synchronization of peripheral clocks. It is the primary hormonal signal for the onset of the biological night.