DSIP (Delta Sleep-Inducing Peptide): Research Overview and Evidence Quality

Delta sleep-inducing peptide (DSIP) is a nine-amino-acid neuropeptide that has been studied since the 1970s. It is one of the more curious compounds in the research peptide space, because the original name describes an effect that later studies could not consistently reproduce, and because no dedicated receptor for it has ever been firmly identified. This overview covers what is known and why the literature is considered mixed.

Sequence and Properties

DSIP has the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, and a molecular weight of about 849 Da. It is small and hydrophilic and is typically supplied as a lyophilised powder. Our DSIP 10mg listing is a preorder, with the specification on the product page.

History

DSIP was first described in the 1970s by a Swiss group, who isolated it from the cerebral venous blood of rabbits during induced slow-wave sleep and reported that infusing it into other rabbits increased delta-wave activity on EEG. That finding gave the peptide its name. Follow-up work in the following decades examined its presence in tissues, its breakdown, and its effects in other models.

What Later Research Reported

The picture became more complicated:

• •Results varied between laboratories. Studies in different species, using different routes and timings, reported differing or null effects on sleep architecture.
• •No gene or receptor has been definitively identified. Unlike most peptide hormones, there is no well-characterised DSIP precursor gene or receptor, which makes the mechanism hard to study.
• •Other activities were reported. Preclinical work has examined links to stress and neuroendocrine axes, including the hypothalamic-pituitary-adrenal axis, and to other physiological systems.
• •Stability is an issue. The peptide is broken down quickly by enzymes, which complicates interpretation of in-vivo results.

A reasonable reading is that DSIP is a real, characterised molecule whose physiological role is unclear. This is typical of older neuropeptides, and it is one reason to read primary sources rather than summaries. See peptide hype vs peptide science.

Where It Sits Among Neuropeptides

See Semax research overview for the other major neuropeptide in the catalogue.

Quality and Handling

Because DSIP is small and enzymatically labile, handling matters: store lyophilised material cold and dry. See the peptide storage guide, and check identity and purity on a batch-specific COA. See how to read a peptide COA.

Regulation

Verify the current status of any peptide against the Poisons Standard. "Research use only" is not an exemption. See are research peptides legal in Australia.

Frequently Asked Questions

What does DSIP stand for?

Delta sleep-inducing peptide, named after the delta-wave EEG activity reported in the original experiments.

Is DSIP the same as a sleep medicine?

No. It is a research compound with an inconsistent evidence base and no approved therapeutic use.

What is the DSIP sequence?

Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (WAGGDASGE).

Disclaimer: All compounds referenced are supplied for in-vitro laboratory research only and are not for human or veterinary use. This article is educational and is not medical advice.