PATHOLOGY

Detailed explanation-1: -Melatonin. SCN directly interacts with the pineal gland through the sympathetic neurons of the superior cervical ganglion [83]; in turn, the rhythmic activity of the SCN determines the release of melatonin, which directly correlates with day length.

Detailed explanation-2: -Melatonin Synthesis, Storage and Release Melatonin provides a circadian and seasonal signal to the organisms in vertebrates. Melatonin is produced from serotonin (made from tryptophan), through a cascade of enzymatic reactions (Figure 1).

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).