Selank + Semax Nootropic Peptide Stack — Research Compound Overview

Selank (TKPRPGP; Thr-Lys-Pro-Arg-Pro-Gly-Pro; MW 751.87 Da; CAS 129954-34-3) is a synthetic heptapeptide derived from tuftsin (Thr-Lys-Pro-Arg), an endogenous tetrapeptide produced by IgG cleavage in the spleen with known immunomodulatory properties. The Pro-Gly-Pro C-terminal extension stabilizes Selank against peptidase degradation. Selank's proposed CNS mechanisms: (1) GABA-A receptor potentiation — Selank modulates GABA-ergic tone, producing anxiolytic-like effects in animal models without the sedation, dependence, or cognitive impairment typical of benzodiazepines; (2) BDNF upregulation — published data shows Selank increases BDNF mRNA and protein expression in limbic and prefrontal regions of rodent models; (3) Modulation of serotonin, dopamine, and enkephalin systems — gene expression studies in rat brain report Selank-induced changes in neurotransmitter synthesis and receptor gene transcription; (4) Anti-stress and HPA axis modulation — Selank attenuates stress-induced corticosterone elevation and behavioral anxiety metrics in rodent models. Selank received clinical investigation status in Russia for anxiety and cognitive disorders.

Semax (MEHFPGP; Met-Glu-His-Phe-Pro-Gly-Pro; MW 887.03 Da; CAS 80714-61-0) is a synthetic heptapeptide derived from ACTH(4-10) — the core behavioral/cognitive-active fragment of adrenocorticotropin — with the same Pro-Gly-Pro C-terminal stabilization extension as Selank. Semax's proposed CNS mechanisms: (1) BDNF, VEGF, and NGF expression — Semax is one of the most studied short-peptide BDNF/NGF inducers in pre-clinical literature; intranasal/subcutaneous Semax significantly upregulates neurotrophic factor mRNA and protein in hippocampus, prefrontal cortex, and striatum; (2) Dopaminergic modulation — Semax modulates dopamine turnover in mesolimbic and nigrostriatal systems, with published effects on working memory, attention, and motivation in rodent models; (3) Neuroprotection — published ischemia models (MCAO/carotid occlusion in rodents) report Semax reduces infarct volume, cognitive deficits, and markers of oxidative damage; (4) Serotonergic effects — Semax modulates 5-HT receptor expression. Semax has clinical registration in Russia for stroke recovery and cognitive disorders.

The Selank + Semax research combination captures complementary CNS targets: Selank's GABA-ergic anxiolytic mechanism addresses the anxiety/over-arousal axis, while Semax's BDNF/VEGF/dopaminergic mechanism addresses the cognitive and neurotrophic axis. Both compounds upregulate BDNF — potentially amplifying this shared pathway additively when combined. Research interest in the stack arises from the complementarity: anxiety and cognitive function frequently co-occur in stress/neurological research models, and a compound pair addressing both axes (anxiolytic without sedation + cognitive/neurotrophic without stimulant effects) represents a research design opportunity. Direct published combination studies are limited; the individual compound literatures (each with dozens to hundreds of publications) are the primary evidence base. DMV Research supplies Selank and Semax as individual lyophilized research compounds with per-batch COA confirming identity and purity.