Delta sleep-inducing peptide is a nine-amino-acid sequence, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (WAGGDASGE), first isolated in the 1970s from the cerebral venous blood of rabbits in induced slow-wave sleep. Molecular formula C35H48N10O15, molecular weight 848.8 g/mol.
The name records what researchers were looking for when they found it rather than a settled account of what it does. Delta-wave activity was the endpoint being measured in the original isolation work, and the label has persisted through five decades of subsequent research that has complicated the picture considerably.
Research context
The literature is unusually broad for a nine-residue sequence. Alongside sleep architecture, published work examines DSIP in stress-response and corticotropin models, thermoregulation, nociception, and antioxidant endpoints.
That breadth cuts both ways. It has kept the peptide in circulation as a research subject, but the mechanism remains poorly defined — no specific receptor has been conclusively identified, which is unusual for a sequence studied this long. Researchers surveying the literature should expect a fragmented evidence base rather than a convergent one.
For a fuller treatment of the sequence, published models and technical data, see the DSIP research guide.
Specification
CAS number 62568-57-4. Supplied as a white lyophilized powder, soluble in water. This batch assayed at 99.24% purity, verified by HPLC and LC-MS at ILS Lab.
Handling
Reconstitute with bacteriostatic or sterile water, introducing the diluent against the vial wall and swirling gently rather than shaking. Store lyophilized at −20°C protected from light; refrigerate at 2–8°C once reconstituted.
Ships with a batch-specific Certificate of Analysis. Cross-check the batch ID printed on your vial against the CoA before use — see the guide to reading a CoA if you are unfamiliar with the format.
Frequently asked questions about DSIP
Does DSIP have an identified receptor?
No. Despite five decades of study, no specific receptor has been conclusively identified — which is genuinely unusual for a sequence researched this long. That absence is the central open question in the DSIP literature and the reason the mechanism remains poorly defined. Researchers should treat the mechanistic picture as unresolved rather than assume a receptor-mediated model.
Why is it called delta sleep-inducing peptide?
The name records the experiment that found it, not a settled account of what it does. It was isolated in the 1970s from the cerebral venous blood of rabbits in induced slow-wave sleep, and delta-wave activity was the endpoint being measured. Subsequent research has broadened the picture considerably — stress response, thermoregulation, nociception, antioxidant endpoints — but the original name persisted.
How solid is the DSIP evidence base?
Fragmented rather than convergent. The literature spans an unusually wide range of endpoints for a nine-residue peptide, and that breadth has kept it in circulation as a research subject without producing a unifying mechanism. Researchers surveying it should expect scattered findings across several fields rather than a coherent body of work building in one direction.
How is DSIP reconstituted and stored?
Bacteriostatic or sterile water; it is water-soluble and needs no acidic diluent. Introduce the diluent against the inner wall of the vial and swirl gently rather than shaking. Store lyophilized at −20°C protected from light; refrigerate at 2–8°C once reconstituted and avoid repeated freeze-thaw cycles.
Research use only. Not for human or veterinary use, not for use in diagnostic procedures, and not evaluated by the U.S. Food and Drug Administration.
