Social Rejection in Adolescent Rats Changed Pain Sensitivity Through the Endocannabinoid System

Adolescent rats who experienced social rejection from unresponsive play partners developed reduced pain sensitivity, and blocking CB1 receptors prevented both the social stress and the pain changes.

Schneider, Peggy et al.·European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology·2016·Preliminary EvidenceAnimal StudyAnimal Study
RTHC-01261Animal StudyPreliminary Evidence2016RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Researchers modeled adolescent social rejection by pairing adolescent Wistar rats with Fischer 344 rats, a strain known for being unresponsive to play solicitations. The Wistar adolescents showed clear signs of social distress: increased ultrasonic vocalizations at 50 kHz (associated with positive/seeking states) and increased play attacks, suggesting they were trying harder to engage their unresponsive partners.

After these experiences, the socially rejected rats showed decreased pain sensitivity to thermal stimuli. A low dose of the CB1 receptor blocker SR141716 given before the social encounter prevented both the compensatory social behaviors and the subsequent pain changes.

This demonstrates that the endocannabinoid system mediates the link between social pain (rejection) and physical pain processing, providing a biological explanation for why social and physical pain overlap.

Key Numbers

Wistar rats paired with Fischer 344 partners showed increased 50 kHz ultrasonic vocalizations and increased play attacks. Social rejection reduced thermal pain sensitivity. Sub-threshold CB1 blockade prevented both social and pain-related effects.

How They Did This

Female adolescent Wistar rats were paired with either same-strain partners (control) or Fischer 344 rats (social rejection model) for acute social interaction sessions. Behavioral analysis included play attacks, ultrasonic vocalizations, and pain sensitivity testing. The CB1 receptor antagonist SR141716 was administered at a sub-threshold dose before social encounters to test endocannabinoid involvement.

Why This Research Matters

The overlap between social and physical pain is well documented in humans but poorly understood mechanistically. This study identifies the endocannabinoid system as a key mediator, suggesting that the same system activated by cannabis is involved in processing the pain of social rejection during the sensitive adolescent period.

The Bigger Picture

Adolescence is a period of heightened sensitivity to both social rejection and the effects of cannabinoids. This study connects these two vulnerabilities through a common biological system. The finding that social pain modifies physical pain through endocannabinoid signaling may help explain why some adolescents turn to cannabis after social difficulties.

What This Study Doesn't Tell Us

This was a rodent study, and social dynamics in rats may not fully model human adolescent rejection. Only female rats were tested. The CB1 blocker was given before the social encounter, so it is unclear whether it would reverse already-established changes. The Fischer 344 pairing is a model of social rejection but not identical to human peer rejection.

Questions This Raises

  • ?Does chronic adolescent social rejection produce lasting endocannabinoid system changes?
  • ?Could endocannabinoid system dysfunction explain the link between peer rejection and substance use in human adolescents?
  • ?Would these findings differ in male rats?

Trust & Context

Key Stat:
CB1 receptor blockade prevented both the social stress response and the altered pain sensitivity from peer rejection.
Evidence Grade:
Preliminary evidence from a well-controlled animal study demonstrating a clear mechanism, though translation to human adolescent social experiences requires further research.
Study Age:
Published in 2016. The intersection of social neuroscience and the endocannabinoid system continues to be explored.
Original Title:
Adolescent social rejection alters pain processing in a CB1 receptor dependent manner.
Published In:
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology, 26(7), 1201-12 (2016)
Database ID:
RTHC-01261

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

How are social pain and physical pain connected?

This study shows they share a common biological system: the endocannabinoid system. Blocking CB1 receptors prevented both the social stress response to rejection and the subsequent changes in physical pain sensitivity, suggesting these experiences are neurologically intertwined.

Could this explain why some teens use cannabis after social difficulties?

Potentially. If social rejection activates the endocannabinoid system to modulate pain, teens who experience frequent rejection might have altered endocannabinoid tone, which cannabis could temporarily normalize. This is speculative but consistent with the findings.

Read More on RethinkTHC

Cite This Study

RTHC-01261·https://rethinkthc.com/research/RTHC-01261

APA

Schneider, Peggy; Pätz, Monique; Spanagel, Rainer; Schneider, Miriam. (2016). Adolescent social rejection alters pain processing in a CB1 receptor dependent manner.. European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology, 26(7), 1201-12. https://doi.org/10.1016/j.euroneuro.2016.04.007

MLA

Schneider, Peggy, et al. "Adolescent social rejection alters pain processing in a CB1 receptor dependent manner.." European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology, 2016. https://doi.org/10.1016/j.euroneuro.2016.04.007

RethinkTHC

RethinkTHC Research Database. "Adolescent social rejection alters pain processing in a CB1 ..." RTHC-01261. Retrieved from https://rethinkthc.com/research/schneider-2016-adolescent-social-rejection-alters

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 RethinkTHC 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.