Question

During what stage of sleep is growth hormone released?

A. Stage N1

B. REM sleep

C. slow-wave

D. N2

Answer 1

During slow wave sleep or NREM stage 3 sleep GH(growth hormone released.

The temporal relation between the first few hours of sleep and the secretion of growth hormone (GH), which is present in normal persons of both sexes from early childhood until late adulthood, is studied. In adults the most reproducible pulse of GH secretion occurs shortly after the onset of sleep in association with the first phase of slow-wave sleep (SWS) (stages III).

In men approximately 70% of the GH pulses during sleep coincide with SWS, and the amount of GH secreted during these pulses correlates with the concurrent amount of SWS.

Secretion of GH appears to be primarily dependent on the release of growth hormone-releasing-hormone(GHRH). Rodent and human studies have shown that growth hormone-releasing hormone injections decrease wakefulness and increase SWS.