A nonapeptide isolated from cerebral venous blood during slow-wave sleep, named for an effect that has proved harder to reproduce than to describe.
- Sequence
- Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (WAGGDASGE)
- Molecular formula
- C35H48N10O15
- Molecular weight
- 848.8 g/mol
- CAS number
- 62568-57-4
- Appearance
- white lyophilised powder
- Strengths available
- 5mg, 10mg per vial
- Purity
- ≥99% by HPLC, identity confirmed by mass spectrometry
- Released against
- the Certificate of Analysis for its own batch
About DSIP
Delta sleep-inducing peptide is the nonapeptide Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, isolated in 1977 from the cerebral venous blood of rabbits in which slow-wave sleep had been induced electrically. The name records the original observation rather than a settled mechanism.
Nearly five decades later, no receptor has been identified, and that is the single most important thing to know about it. Without a receptor there is no binding assay, no selectivity profile and no structure-activity programme of the kind that organises the literature on, for example, the growth hormone secretagogues. The sequence is small, acidic from two carboxylate side chains, and has no residue that resists proteolysis, consistent with the very short half-life reported for it.
What the research covers
Work covers sleep architecture, including slow-wave proportion, latency and continuity measured by EEG, which is the only readout that addresses the claim it is named for. Those findings are genuinely mixed: some studies report changes, others find none, and the inconsistency has not been resolved. A laboratory working here should treat a null result as a realistic outcome rather than an anomaly.
Better supported, though still preliminary, is a stress-protective and homeostatic framing: corticotropin and cortisol modulation, antinociception, reported effects on withdrawal states, and thermoregulatory observations. Authors who treat DSIP as a general modulator of adaptive responses rather than specifically a sleep peptide are, on the available evidence, on firmer ground. Published work is indexed on PubMed.
Handling DSIP
Supplied lyophilised. A nine-residue peptide with no stabilising modification is among the less robust sequences in this catalogue: short half-life in biological matrices and adsorption losses at low concentration.
Prepare working solutions immediately before use, use low-binding plasticware, and keep reconstituted material cold and unfrozen. Store sealed vials at -20°C. Solvent options are under reconstitution supplies.
Other formats
DSIP is also supplied as a metered 15ml DSIP nasal spray, where no reconstitution step is needed.
Common questions about DSIP
What does DSIP stand for?
Delta sleep-inducing peptide, named after the slow-wave (delta) sleep present when it was first isolated.
Does DSIP reliably affect sleep?
The evidence is mixed. Some studies report changes in sleep architecture and others find none, so the effect is not established.
Why does the lack of a receptor matter?
Without a known receptor there is no binding assay or selectivity profile, so mechanisms cannot be pinned down the way they can for most peptides.
What else is DSIP studied for?
Stress and corticosteroid responses, pain thresholds, withdrawal states and thermoregulation, under a broader homeostatic framing.
How should DSIP be stored?
Sealed vials at -20°C. Solutions are made immediately before use, kept cold and not frozen.
