Quick answer: Semax, Selank, and Pinealon are three peptides studied in cognition and stress-response research — the same three are examined at greater length in our nootropic peptide research overview. Semax is researched mainly for BDNF and dopamine modulation tied to focus and neuroplasticity; Selank for anxiolytic, GABA/enkephalin-related signaling; and Pinealon for neuroprotective, antioxidant research in brain cells. They’re often studied as complementary tools. Sold for research use only. Related circadian and neuroprotective work is covered in DSIP and Epithalon.
What each is studied for
Semax is a synthetic peptide derived from a fragment of ACTH (adrenocorticotropic hormone). Research describes it as a multi-pathway neurotrophic compound acting on BDNF, NGF, NT-3, dopamine, and serotonin. A well-replicated animal finding is that a single intranasal dose rapidly increases hippocampal BDNF-mRNA and TrkB phosphorylation, which is why it’s a frequent tool in cognition, mood, and neuroplasticity research.
Selank is a synthetic analogue of the immunomodulatory peptide tuftsin. Its research centers on anxiolytic (anti-anxiety) signaling: it upregulates BDNF in hippocampal tissue and inhibits enkephalinase, extending enkephalin half-life and potentiating endogenous opioid tone without stimulating opioid receptors directly. This makes it a common tool in stress and mood research.
Pinealon is a short peptide bioregulator (cytomedine class) studied for neuroprotective and antioxidant activity in brain cells, including research on oxidative-stress resistance and gene-expression regulation in neural tissue.
Why they’re studied together
Semax (neurotrophic/dopaminergic) and Selank (anxiolytic/GABAergic) form a dual-mechanism pair for stress-cognition interaction models. Because anxiety-related stress signaling can suppress BDNF and impair hippocampal neuroplasticity, researchers study Selank’s stress-reduction signaling as potentially complementary to Semax’s neurotrophic effects. Pinealon adds a neuroprotective axis.
What the research literature covers
- BDNF/NGF neurotrophin signaling and TrkB activation
- Dopamine and serotonin modulation (Semax)
- Enkephalinase inhibition and GABAergic anxiolytic pathways (Selank)
- Neuroprotection, oxidative-stress resistance, and neuroinflammation models
- Stress-cognition interaction and multi-target CNS research
Research note: decades of pharmaceutical use in Russia are the best available long-term signal, but formal long-term Western trials do not exist.
Frequently asked questions
What is the difference between Semax and Selank?
Semax is studied mainly as a neurotrophic/dopaminergic compound linked to focus and neuroplasticity (BDNF, dopamine), while Selank is studied mainly as an anxiolytic acting through GABA/enkephalin pathways. See our dedicated Semax vs Selank comparison.
What does Semax do in research?
It is researched for rapidly raising hippocampal BDNF and modulating dopamine and serotonin, making it a tool in cognition, mood, and neuroplasticity studies.
Is Selank an opioid?
No. Selank inhibits enkephalinase to extend the half-life of the body’s own enkephalins; it does not directly stimulate opioid receptors.
What is Pinealon?
A short peptide bioregulator studied for neuroprotective and antioxidant activity in brain cells.
Are these for human use?
No. Portal to Wellness sells these strictly for laboratory and research use only. Nothing here is medical advice.
Primary-literature anchors
Cite primary sources rather than vendor blogs: research on Semax and hippocampal BDNF/TrkB (multiple Russian neuropharmacology papers); Selank anxiolytic and enkephalinase research; Khavinson cytomedine peptide-bioregulator literature for Pinealon. Link via PubMed.
For research use only. Not for human or veterinary use, diagnosis, treatment, or prevention of any condition. Not evaluated by the FDA. Author: Charles Fowler. Last updated: May 2026.