PeptideHormone

Delta sleep-inducing peptideDSIP

A naturally occurring nonapeptide named for a sleep effect that never fully replicated.

Research peptideLimited

Identity

Class
Endogenous nonapeptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu)
Source
Isolated from mammalian brain and blood; distribution poorly mapped
Receptor
No established receptor; no defined signaling pathway

Key properties

Molecular weight
~848.8 Da

Approximate values for the native hormone. Engineered analogs are often deliberately larger and far longer-acting.

Mechanism

DSIP was isolated in the 1970s from the cerebral venous blood of sleeping rabbits and named for the delta-wave sleep it appeared to induce. Decades later it remains, in the words of its own review literature, an 'unresolved riddle': it is genuinely endogenous, yet no receptor, no biosynthetic gene, and no consistent physiological role have been pinned down, and the original sleep effect has proven hard to reproduce.

Reference notes

  • It is one of the rare 'research peptides' that is unambiguously endogenous — the puzzle is what, if anything, it actually does.
  • Reported effects sprawl across sleep, stress buffering, thermoregulation, and antioxidant activity, but none are firmly established.
  • Its plasma half-life is extremely short, which complicates any simple dose-to-effect story.

Common questions

What is Delta sleep-inducing peptide (DSIP)?
A naturally occurring nonapeptide named for a sleep effect that never fully replicated. Structurally it is Endogenous nonapeptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu).
How does DSIP work?
DSIP was isolated in the 1970s from the cerebral venous blood of sleeping rabbits and named for the delta-wave sleep it appeared to induce. Decades later it remains, in the words of its own review literature, an 'unresolved riddle': it is genuinely endogenous, yet no receptor, no biosynthetic gene, and no consistent physiological role have been pinned down, and the original sleep effect has proven hard to reproduce.
How strong is the evidence for DSIP?
PeptideHormone grades DSIP at the "Limited" evidence tier — the evidence is sparse, older, or mostly community-reported. It is catalogued as a community research peptide outside the approved-drug system, and the tier is an editorial judgment about the public literature that can change as the science does.

Selected literature

Curated peer-reviewed reviews, sourced from PubMed. Selected for relevance, not exhaustive — open any entry on PubMed for the full record and its primary citations.

  1. 1.Delta sleep-inducing peptide (DSIP): a still unresolved riddle · Journal of neurochemistry, 2006 · PMID 16539679
  2. 2.Delta-sleep-inducing peptide (DSIP): a review · Neuroscience and biobehavioral reviews, 1984 · PMID 6145137
  3. 3.Delta sleep-inducing peptide · European journal of anaesthesiology, 2001 · PMID 11437870