For Research Use Only. Not for human consumption. The following summarizes published preclinical literature for laboratory research purposes only.
What It Is
Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) is a synthetic heptapeptide developed at the Institute of Molecular Genetics of the Russian Academy of Sciences — the same research institution responsible for Semax. Structurally, Selank is an analogue of tuftsin, an endogenous tetrapeptide (Thr-Lys-Pro-Arg) generated by enzymatic cleavage of immunoglobulin G that was originally studied for immunomodulatory activity; Selank extends the tuftsin sequence with a Pro-Gly-Pro C-terminal addition that increases enzymatic stability and alters its central nervous system activity profile in animal and human research contexts (Zozulia et al., Bull Exp Biol Med, 2001). Like Semax, Selank has an extensive Russian research literature and a Russian Federation regulatory registration history; it holds no FDA approval and no U.S. clinical indication.
Summary of Published Preclinical and Clinical Research
Mouse-model research examining differing “phenotypes of emotional and stress reactions” found that Selank altered behavioral stress-reactivity measures alongside changes in plasma enkephalin-degrading enzyme activity, supporting a peptidase-inhibition-linked behavioral effect across genetically distinct stress-response phenotypes (Semenova et al., Bull Exp Biol Med, 2002).
In an in-vitro enzyme assay, a Russian study characterized plasma enkephalin metabolism and enkephalinase activity, and reported that Selank dose-dependently inhibited enzymatic hydrolysis of plasma enkephalin (IC50 ≈15 µM) relative to the peptidase inhibitors bacitracin and puromycin (Zozulia et al., Bull Exp Biol Med, 2001). This Russian-language literature is cited here as documented research history in that jurisdiction, not as evidence supporting any therapeutic or consumer use claim in the U.S. market.
Proposed Mechanism of Action
The primary mechanistic hypothesis advanced in the peer-reviewed literature is enkephalinase (enkephalin-degrading enzyme) inhibition: Selank dose-dependently inhibits the enzymatic breakdown of endogenous enkephalins in plasma, a proposed route by which it may influence downstream opioidergic signaling through a mechanism distinct from GABA-A-targeted compounds (Zozulia et al., 2001). Because Selank derives from tuftsin, a peptide with documented immunomodulatory activity, researchers have also investigated concurrent immune-parameter changes alongside behavioral endpoints in research cohorts, suggesting a possible dual neuroimmune mechanism under continued study.
Research Use & Handling Note
Selank is supplied as a lyophilized powder for laboratory research use only — in-vitro assays and animal-model protocols. This product is not intended for, and must not be used for, human administration, human consumption, veterinary use, or any diagnostic or clinical purpose.