What DSIP is, in plain English.
DSIP, delta sleep-inducing peptide, is a chain of nine amino acids in the order Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, with the molecular formula C35H48N10O15, a molecular weight of about 848.8 g/mol and the CAS number 62568-57-4. It was isolated in the 1970s from the cerebral venous blood of sleeping rabbits by a Swiss group studying how sleep states transfer between animals. Its name comes from that original work: infused into other rabbits, it was associated with delta-wave, slow-wave activity on the EEG. It has since been detected in human tissue and fluids. Half a century on it remains a research peptide with an unsettled mechanism. No gene, precursor protein or receptor for it has been identified, which is unusual for a peptide studied this long, and the sleep findings themselves have been contradictory from one study to the next. It is commonly researched for its part in sleep architecture, in the stress response and in the endocrine rhythms that run alongside sleep, and it has also been studied in pain and withdrawal models. The human evidence is limited and mixed, and it is not a licensed medicine in the UK, the EU or the US. Supplied as 5mg of freeze-dried powder per vial, for reconstitution with bacteriostatic water; store at 2–8°C.
