MICROANATOMY

Detailed explanation-1: -Melatonin is the only known hormone synthesized by the pineal gland and is released in response to darkness hence the name, “hormone of darkness” [10]. Melatonin provides a circadian and seasonal signal to the organisms in vertebrates.

Detailed explanation-2: -Melatonin is an important hormone in circadian synchronization. This hormone is involved in many biological and physiological regulations in the body. It is an effective hormone for human biorhythm (circadian rhythm).

Detailed explanation-3: -In humans and most diurnal mammals, melatonin is secreted at night with a robust circadian rhythm and maximum plasma levels that occur around 3 to 4 AM. The daily rise of melatonin secretion correlates with a subsequent increase in sleep propensity about 2 hours before the person’s regular bedtime.

Detailed explanation-4: -The main function of the pineal gland is to receive and convey information about the current light-dark cycle from the environment via the production and secretion of melatonin cyclically at night (dark period) (6, 7).

Detailed explanation-5: -Melatonin is a natural hormone that’s mainly produced by your pineal gland in your brain. It plays a role in managing your sleep-wake cycle and circadian rhythm.