PE 22-28
EmergingLinear heptapeptide
PE 22-28 is a synthetic peptide derived from the pituitary adenylate cyclase-activating polypeptide (PACAP) that has been studied for its effects on phosphodiesterase 5 (PDE5) inhibition. Published research has investigated its effects on cGMP signaling pathways and smooth muscle relaxation. RaysunPeptide supplies PE 22-28 for qualified research and laboratory applications.
Mechanism of Action
Selectively blocks TREK-1 potassium channels (IC50: 0.12 nM). Enhances serotonin neurotransmission in dorsal raphe nucleus, triggering CREB activation and hippocampal neurogenesis.
Key Benefits
Molecular Data
Dosing Protocols
| Goal | Dose | Frequency | Route |
|---|---|---|---|
| Antidepressant Effect | 50-200mcg | Once daily | SubQ |
| Neurogenesis Support | 100-200mcg | Once daily | SubQ |
Research Indications
Mental Health
Primary research focus with rapid effects in behavioral models within 4 days.
Anxiolytic properties demonstrated in preclinical anxiety models.
Neurogenesis
Nearly doubles BrdU-positive cells after 4-day treatment.
Promotes new synapse formation through CREB activation.
Cognition
Hippocampal and prefrontal cortex TREK-1 expression supports memory.
Potential ischemic protection and neuronal survival support.
Peptide Interactions
Both enhance serotonergic pathways; monitor for excessive activity.
Complementary neurogenesis and cognitive support.
Different mechanisms for anxiety and mood support.
Complementary neuroplasticity pathways.
Different mechanisms, no contraindications.
Serotonin syndrome risk.
What to Expect
Side Effects & Safety
Common (Generally Mild)
- •No effects on TREK-2, TRAAK, TASK-1 channels observed
- •No cardiac dysfunction or seizures in preclinical studies
Stop Signs (Seek Medical Attention)
- ⚠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
References
PE-22-28 IC50 0.12 nM vs 40-60 nM for Spadin; ~23 hour duration.
Original discovery of TREK-1 blockade as antidepressant mechanism.
TREK-1 knockout mice show depression-resistant behavior in 5 tests.
FAQs
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.
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.
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.
