A synthetic neuropeptide that promotes sleep onset and maintenance. Derived from hypothalamic sleep-inducing factor.
Delta Sleep Inducing Peptide (DSIP) is a naturally occurring nonapeptide first isolated from rabbit brain in 1977. It promotes a particular type of sleep characterized by increased delta rhythm in the EEG in various species including humans. DSIP can freely cross the blood-brain barrier and is readily absorbed from the gut without being denatured by enzymes.
DSIP promotes sleep by increasing delta rhythm activity in the EEG. It is normally synthesized in the hypothalamus and targets multiple sites including some within the brainstem. The exact mechanisms of its sleep-promoting effects remain unknown.
A double-blind study on 16 chronic insomnia patients used intravenous DSIP (25 nmol/kg) over three consecutive nights.