Substance P and Its Receptor Drive Central Sensitization in Chronic Pain

The substance P/NK1 receptor system is involved in central sensitization — a key mechanism of chronic pain — with evidence from nerve injury mouse models showing its role in maintaining persistent pain.

Chen, Juan et al.·Neuroscience letters·2026·
RPEP-149832026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Not classified
Evidence
Not graded
Sample
Not reported

What This Study Found

The substance P/NK1R system is involved in central sensitization in chronic pain, as demonstrated in a spared nerve injury mouse model.

Key Numbers

How They Did This

Preclinical study using spared nerve injury (SNI) mouse model with behavioral, molecular, and pharmacological analysis of substance P/NK1R system.

Why This Research Matters

Despite decades of research, effective treatments for chronic pain remain elusive. Clarifying substance P's role in central sensitization could revive interest in NK1R antagonists or related drug targets.

The Bigger Picture

Substance P was once a major drug target for pain, but NK1R antagonists largely failed in clinical trials. This new evidence of its role in central sensitization could lead to more targeted approaches that succeed where earlier drugs failed.

What This Study Doesn't Tell Us

Mouse model may not fully replicate human chronic pain; SNI represents neuropathic pain specifically; NK1R antagonists have previously failed in human pain trials.

Questions This Raises

  • ?Could next-generation NK1R antagonists targeting central sensitization specifically succeed where earlier drugs failed?
  • ?Is substance P's role in central sensitization different from its role in acute pain transmission?

Trust & Context

Key Stat:
30%+ affected worldwide Chronic pain driven partly by substance P/NK1R-mediated central sensitization
Evidence Grade:
Preclinical mouse study — provides mechanistic evidence but translational relevance to human chronic pain needs validation.
Study Age:
Published in 2026, re-examining a classic neuropeptide target with modern techniques.
Original Title:
Involvement of substance P/NK1 receptor system in central sensitization in chronic pain.
Published In:
Neuroscience letters, 871, 138464 (2026)
Authors:
Chen, Juan(3), Lai, Yimin, Li, Wei(4)
Database ID:
RPEP-14983

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

What is central sensitization?

Central sensitization is when the nervous system becomes hypersensitive to pain, amplifying signals so that normal touch can feel painful and minor injuries cause severe pain. It's a major driver of chronic pain conditions.

What is substance P?

Substance P is a neuropeptide (small protein) released by nerve cells that transmits pain signals. It binds to NK1 receptors and has been studied for decades as a potential target for pain treatment.

Read More on RethinkPeptides

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Cite This Study

RPEP-14983·https://rethinkpeptides.com/research/RPEP-14983

APA

Chen, Juan; Lai, Yimin; Li, Wei. (2026). Involvement of substance P/NK1 receptor system in central sensitization in chronic pain.. Neuroscience letters, 871, 138464. https://doi.org/10.1016/j.neulet.2025.138464

MLA

Chen, Juan, et al. "Involvement of substance P/NK1 receptor system in central sensitization in chronic pain.." Neuroscience letters, 2026. https://doi.org/10.1016/j.neulet.2025.138464

RethinkPeptides

RethinkPeptides Research Database. "Involvement of substance P/NK1 receptor system in central se..." RPEP-14983. Retrieved from https://rethinkpeptides.com/research/chen-2026-involvement-of-substance-pnk1

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.