Evidence map›Paper›PMID 42600850›Full record

ArticleNeurotoxicology2026

Xylazine, veterinary anesthetic and recreational drug adulterant, reduces cephalic regeneration and alters defensive responding in planarians.

Amy D Stringer, Meghana Dachepalli, Scott M Rawls

Abstract read
In one paragraph

Article in Neurotoxicology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Amy D StringerCenter for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA; Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA. Electronic address: amy.stringer@temple.edu.
Meghana DachepalliCenter for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA; College of Science and Technology, Temple University, Philadelphia, PA, USA.
Scott M RawlsCenter for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA; Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.

Funding

TRAINING PROGRAM: DRUGS OF ABUSE RELATED NEUROPEPTIDEST32DA007237 · NIDA · TEMPLE UNIV OF THE COMMONWEALTH · PI ELLEN M UNTERWALD · 1988 to 2026
$10.6M
Xylazine effects on methamphetamine-induced behavioral alterations in ratsR21DA062400 · NIDA · TEMPLE UNIV OF THE COMMONWEALTH · PI SCOTT M. RAWLS · 2025 to 2026
$436k
NIDA NIH HHS R21 DA062400NIDA NIH HHS T32 DA007237
6 · The paper itself

Abstract

Xylazine is a veterinary anesthetic and α2-adrenoceptor agonist found in illicit drug supplies. Injection of opioids adulterated with xylazine is correlated with necrotic tissue injury and a withdrawal syndrome including anxiety. Planarians are flatworms with a simple nervous system and no circulatory system that exhibit several characteristics, including regenerative capacity and negative phototaxis (light avoidance). Because regeneration reflects tissue repair and negative phototaxis constitutes defensive behavior, planarians provide a simple in vivo system to explore possible effects of xylazine on planarian wound repair and anxiety-like behavior. Using planarians, we investigated the effects of xylazine on cephalic regeneration and defensive responding (i.e., determined by time spent on light side of a dish divided into light and dark compartments). In decapitated planarians, chronic xylazine exposure (0.001-0.1 µM, over 2 weeks) reduced head regeneration rate. For intact worms, acute xylazine (1 µM, 5 min) caused a reduction in defensive responding (i.e., increased time in light) that was abolished by yohimbine (0.001 µM), an α2-adrenoceptor antagonist. Clonidine (0.01-1 µM), another α2-adrenoceptor agonist, mimicked xylazine's defensive responding effects. We next assessed effects of xylazine withdrawal on defensive responding. Early xylazine abstinence (0.01-1 µM, 5 and 30 min), like acute xylazine, reduced defensive responding. In contrast, during later xylazine abstinence (0.001-1 µM, 60 min), defensive responding robustly increased with no significant changes in motility. Our data show that xylazine impairs planarian regeneration and bidirectionally impacts planarian defensive behaviors with distinct acute and withdrawal-dependent effects. These results suggest that some effects of xylazine on tissue injury and anxiety-like behavior are conserved in planarians.

Indexed as

Adrenergic alpha-2 Receptor AgonistsIllicit DrugsPlanariansRegenerationVeterinary DrugsXylazineAnimalsDose-Response Relationship, DrugAdrenergic alpha-2 Receptor AgonistsIllicit DrugsVeterinary DrugsXylazineAdrenergicAnxiolyticDefensive respondingPlanariaRegenerationXylazine

Identifiers

PMID42600850
PMCPMC13552069

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.