Selank

What Is Selank?

Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) developed at the Institute of Molecular Genetics of the Russian Academy of Sciences in the late 1980s as a stable analogue of tuftsin, an endogenous immunomodulatory tetrapeptide cleaved from IgG. The Pro-Gly-Pro C-terminal extension blocks enzymatic degradation, allowing Selank to cross the blood-brain barrier and persist long enough to act centrally, where native tuftsin is degraded before arrival.

The anxiolytic mechanism runs through GABAergic modulation: Selank upregulates GABA-A receptor expression and amplifies inhibitory tone without binding the benzodiazepine site, which is why the Russian trials report anxiolysis without sedation, tolerance, or dependence. A serotonergic arm increases brain serotonin metabolism (measured via 5-HIAA), and BDNF is upregulated in the hippocampus, the neuroplasticity layer that overlaps downstream with SSRI mechanisms. Selank also retains the immunomodulatory activity of its tuftsin parent, with published effects on interferon production and cytokine balance. It is a registered anxiolytic in Russia, where it has been studied as an alternative to benzodiazepines in generalised anxiety disorder since the late 1990s.