The Peptide Reference
The Peptide Reference
References
Reference/Linear heptapeptide

PE-22-28

TREK-1 Channel Blocker · Shortened Spadin Analog

research use only

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.

Rapid antidepressant effects within 4 days (preclinical)Hippocampal neurogenesis and synaptogenesisEnhanced serotonergic neurotransmissionExtended ~23 hour duration of action
01

Overview

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.

02

Research indications

What the compound has been studied for, grouped by body system. Effect size is the reported magnitude where it was measured — not a recommendation.

Mental Health2
Depression

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

Large
Anxiety

Anxiolytic properties demonstrated in preclinical anxiety models.

Small
Neurogenesis2
Hippocampal Neurogenesis

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

Large
Synaptogenesis

Promotes new synapse formation through CREB activation.

Moderate
Cognition2
Memory Support

Hippocampal and prefrontal cortex TREK-1 expression supports memory.

Moderate
Neuroprotection

Potential ischemic protection and neuronal survival support.

Small
i

A large effect in a weak study and a small effect in a strong one are different things. Effect size is never evidence of use in people.

Quick factsreference only
Class
Linear heptapeptide
Chain length
7 residues
Molecular weight
773.89 Da
Half-life
~23 h
Typical dose
50-200mcg daily
Frequency
Once daily
Cycle length
4-8 weeks
Storage
Refrigerate at 2-8°C, use within 4-6 weeks
03

Molecular data

Type
Linear heptapeptide
Molecular weight
773.89 Da
Chain length
7 residues
Half-life
1380 min
04

Dosing reference

Doses reported in the literature and by suppliers. These are a record of what has been used in research — reference, never instruction.

ContextRouteAmountFrequency
Antidepressant EffectSubQ50-200mcgOnce daily
Neurogenesis SupportSubQ100-200mcgOnce daily
General UseOralHigher than injectable (specific dose TBD)Daily
General UseIntranasal100-300mcg (estimated)Daily
05

Interactions

SSRIs (Fluoxetine, Sertraline)

Both enhance serotonergic pathways; monitor for excessive activity.

monitor
Semax/NA-Semax

Complementary neurogenesis and cognitive support.

synergistic
Selank

Different mechanisms for anxiety and mood support.

synergistic
Dihexa

Complementary neuroplasticity pathways.

synergistic
BPC-157

Different mechanisms, no contraindications.

compatible
MAOIs

Serotonin syndrome risk.

avoid
06

Quality checklist

  • White to off-white lyophilized powder
  • Clear, colorless reconstituted solution
  • Certificate of Analysis with >98% purity
  • Proper cold-chain shipping
  • !Research compound only, not FDA-approved
  • !Quality varies by supplier
  • ×Cloudy, discolored, or particulate appearance
  • ×Clumped or sticky powder indicating moisture damage
07

What to expect

Days 1-4Measurable antidepressant effects in preclinical models
Weeks 1-2Neurogenesis and synaptogenesis processes established
Weeks 2-4Potential mood and cognitive improvements emerge
Weeks 4-8Sustained treatment allows full neurogenic effects
08

Safety

Commonly reported2
  • No effects on TREK-2, TRAAK, TASK-1 channels observed
  • No cardiac dysfunction or seizures in preclinical studies
Stop and seek advice5
  • Serotonin syndrome signs
  • Severe persistent headaches
  • Cardiac symptoms
  • Seizure activity
  • Severe mood changes or suicidal ideation
Contraindications2
  • Pregnancy and breastfeeding
  • Concurrent MAOI use
09

FAQ

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.

For research use only. Nothing on this page is medical advice, and no number here is a recommendation to dose.