DSIP

What Is DSIP?

DSIP (Delta Sleep-Inducing Peptide) is a nine-amino-acid neuropeptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) first isolated in 1977 by Schoenenberger and Monnier in Basel from rabbit cerebral venous blood following low-frequency electrical stimulation of the intralaminar thalamic nuclei. It crosses the blood-brain barrier intact and shifts EEG architecture toward slow-wave (delta) activity, with the original characterisation studies reporting roughly a 35% increase in delta activity in neocortex and limbic cortex relative to controls.

DSIP is not a sedative and does not bind GABA receptors directly. Its activity on the sleep-wake system runs through stress-axis dampening (it attenuates stress-induced corticosterone and cortisol elevation), opioid-receptor-adjacent activity (the basis for its study in opioid and alcohol withdrawal models), and direct delta-wave promotion. Plasma half-life is short, roughly 7 to 15 minutes, via aminopeptidase and endopeptidase clearance, while the reported effects on sleep architecture in the animal and small human studies outlast the plasma presence of the peptide by a wide margin.