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PE-22-28 Overview, Dosing & Safety | Peptide Database

PE-22-28 (Mini-Spadin) TREK-1 Channel Blocker | Shortened Spadin Analog Community Research Join others researching PE-22-28 — share findings, ask questions, and learn from real experiences Synthetic heptapeptide derived from Spadin positions 22-28, functioning

Written by Peptide Therapy Guide Editorial Team
For education only

This guide cannot diagnose a condition or recommend a personal treatment plan. Discuss medical questions with a qualified professional.

PE-22-28 (Mini-Spadin)

TREK-1 Channel Blocker | Shortened Spadin Analog

Community Research

Join others researching PE-22-28 — share findings, ask questions, and learn from real experiences

Synthetic heptapeptide derived from Spadin positions 22-28, functioning as potent TREK-1 antagonist with enhanced selectivity and duration versus parent compound. Primary research focus on rapid antidepressant effects.

Selectively blocks TREK-1 potassium channels (IC50: 0.12 nM). Enhances serotonin neurotransmission in dorsal raphe nucleus, triggering CREB activation and hippocampal neurogenesis.

Molecular Data

Glycine

Position 1

Valine

Position 2

Serine

Position 3

Tryptophan

Position 4

Position 5

Leucine

Position 6

Arg (GVSWGLR)

Position 7

Research Indications

Primary research focus with rapid effects in behavioral models within 4 days.

Anxiolytic properties demonstrated in preclinical anxiety models.

Nearly doubles BrdU-positive cells after 4-day treatment.

Promotes new synapse formation through CREB activation.

Hippocampal and prefrontal cortex TREK-1 expression supports memory.

Potential ischemic protection and neuronal survival support.

Dosing Protocols

Subcutaneous injection to abdominal fat or thigh with site rotation.

Antidepressant Effect

50-200mcg

Once daily

SubQ

Neurogenesis Support

100-200mcg

Reconstitution Instructions

PE-22-28 lyophilized powder

Bacteriostatic water

Insulin syringes

Alcohol swabs

1 Inject BAC water slowly down vial wall

2 Gently swirl (do not shake)

3 Store refrigerated 2-8°C

4 Use within 4-6 weeks

Interactions

What to Expect

Side Effects & Safety

Common Side Effects

No effects on TREK-2, TRAAK, TASK-1 channels observed

No cardiac dysfunction or seizures in preclinical studies

Stop Signs - Discontinue if:

Serotonin syndrome signs

Severe persistent headaches

Cardiac symptoms

Seizure activity

Severe mood changes or suicidal ideation

Contraindications

Pregnancy and breastfeeding

Concurrent MAOI use

Quality Checklist

Good Signs

White to off-white lyophilized powder

Clear, colorless reconstituted solution

Certificate of Analysis with >98% purity

Proper cold-chain shipping

Warning Signs

Research compound only, not FDA-approved

Quality varies by supplier

Bad Signs

Cloudy, discolored, or particulate appearance

Clumped or sticky powder indicating moisture damage

Frequently Asked Questions

How much more potent is PE-22-28 compared to full-length Spadin?

PE-22-28 is dramatically more potent—roughly 300-500x more potent than full-length Spadin. This extraordinary difference comes from being a shortened fragment that better mimics the active site. The result is an IC50 of just 0.12 nM for TREK-1 inhibition versus 40-60 nM for Spadin.

Can PE-22-28 work as a standalone antidepressant, or is it just for research?

PE-22-28 shows rapid antidepressant effects in animal models (within 4 days), but it's currently research-only with no human clinical trials completed. It's not approved for therapeutic use. However, the preclinical evidence is strong enough that clinical development may follow if pharmaceutical companies invest in it.

How long does PE-22-28's effect on neurogenesis last?

In preclinical studies, neurogenesis and synaptogenesis establishment begins within 1-2 weeks of treatment. However, we don't know how long effects persist after discontinuation—that depends on sustained CREB activation and whether new neurons survive. Duration data doesn't exist for human use.

Is PE-22-28 safe to combine with SSRIs?

Caution is advised. Both PE-22-28 and SSRIs enhance serotonin. While the interactions section says to 'monitor,' combining them theoretically increases serotonin syndrome risk. Start carefully with your healthcare provider's supervision if considering this combination. Never combine with MAOIs.

References

PE-22-28 IC50 0.12 nM vs 40-60 nM for Spadin; ~23 hour duration. Frontiers in Pharmacology.

Original discovery of TREK-1 blockade as antidepressant mechanism. PLOS Biology.

TREK-1 knockout mice show depression-resistant behavior in 5 tests. Nature Neuroscience.

Related Peptides

Different mechanisms for anxiety and mood support.

Complementary neuroplasticity pathways.

Different mechanisms, no contraindications.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.

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Read sources and limitations before applying a claim.

Community Research

Join others researching Cortagen — share findings, ask questions, and learn from real experiences Cortagen is a Khavinson bioregulator tetrapeptide (AEDP) with primary effects on the brain and central nervous system. Developed at Russia's St. Petersburg Institute of Bioregulation and Gerontology, it regulates inflammatory responses in the nervous system, restores balance between pro- and anti-oxidative processes, and stimulates interleukin-2 expression. Research shows potential benefits for ischemic brain injury recovery, nerve regeneration, and reducing autoimmune reactions affecting the CNS. Cortagen works through epigenetic regulation by penetrating cell nuclei and interacting with DNA to modulate gene expression. In the heart, it affects genes including Pass1, Hsc70, Bmp2, Wnt4, Eps15, and Eps15-rs. It powerfully regulates inflammatory responses in the nervous system, helping restore proper balance between oxidative and anti-oxidative processes. Cortagen stimulates IL-2 expression and helps regulate immune function, particularly by reducing autoimmune reactions.

Source: peptide-db.com ↗

Is PNC-27 closer to clinical trials than other peptide cancer therapies?

Not yet. PNC-27 remains in preclinical research with no human clinical trials initiated as of 2025. While it's been studied since 2000, it hasn't progressed to human testing. That's partly because cancer drug development is slow and partly because peptide therapeutics face delivery challenges that are being actively researched.

Source: peptide-db.com ↗
Practical and safety references

These excerpts are educational, not personalised medical instructions.

Dosage reference

Dosing Protocols

Primary administration route with well-established protocols for direct brain delivery via IV/IM. Small Volume IV Up to 10mL Once daily Undiluted IV slow push over 3 minutes Intramuscular Up to 5mL Undiluted IM injection over 3 minutes Acute Stroke 20-50mL Once daily for 10-21 days IV infusion (diluted to 100mL minimum) Traumatic Brain Injury Once daily for 7-30 days Alzheimer's Disease 10-30mL 5 days weekly for 4 weeks IV injection/infusion (2-4 cycles yearly) Vascular Dementia

Source: peptide-db.com ↗
Side effects

Common Side Effects

Generally well-tolerated in research Possible mild increase in body temperature (less than DNP)

Source: peptide-db.com ↗
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Peptide Therapy Guide Editorial Team

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