A hormone responsible for normal sleep-wake cycle is

Question

A hormone responsible for normal sleep-wake cycle is (A) epinephrine (B) gastrin (C) melatonin (D) insulin

Tardigrade Admin · Accepted Answer

Melatonin is a hormone secreted by pineal gland. Immediately above the optic chiasma (in the brain) in a nucleus, are present melatonin receptors that react to this hormone and synchronise the nucleus to the 24 hrs day/night rhythm, thus informing the brain when it is day and when it is night.

Q. A hormone responsible for normal sleep-wake cycle is

epinephrine

gastrin

melatonin

insulin

Melatonin is a hormone secreted by pineal gland. Immediately above the optic chiasma (in the brain) in a nucleus, are present melatonin receptors that react to this hormone and synchronise the nucleus to the $24$ hrs day/night rhythm, thus informing the brain when it is day and when it is night.