DSIP (Delta Sleep-Inducing Peptide)

What Is DSIP?

Delta Sleep-Inducing Peptide (DSIP) is an endogenous nonapeptide isolated from rabbit cerebral venous blood in 1977. It selectively promotes slow-wave (delta) sleep and modulates multiple neuroendocrine axes. It crosses the blood-brain barrier and has a broad range of research applications beyond sleep induction.

Key Mechanisms

• Delta wave promotion — selectively increases slow-wave sleep proportion without disrupting REM
• HPA axis modulation — reduces cortisol and stress response; potential PTSD research tool
• GH release stimulation — enhances pulsatile GH secretion during sleep
• Antioxidant activity — reduces lipid peroxidation and free radical damage in CNS
• Circadian rhythm normalisation — resets disrupted sleep-wake cycles

Key References

1. Monnier M et al. “Dialysis of sleep and waking factors in blood of the rabbit.” Science, 1977;198:175–177.
2. Graf MV et al. “Delta sleep-inducing peptide — a review of its central activity.” Sleep, 1984;7(4):313–329.