Evidence map›Paper›PMID 39782672›Full record

ArticleCephalalgia : an international journal of headache2025

Sex differences in photophobic behaviors following cortical spreading depression in rats.

Manvir Kaur, Nicholas A Ward, Kelly L Karlage, Catherine W Morgans, Sue A Aicher, Tally M Largent-Milnes

Abstract read
In one paragraph

Article in Cephalalgia : an international journal of headache, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing 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

4 citing papers in PubMed.

  1. Article
  2. Review
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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

6 authors.

Manvir KaurDepartment of Pharmacology, University of Arizona, Tucson, USA.ORCID 0000-0003-4189-033X
Nicholas A WardDepartment of Pharmacology, University of Arizona, Tucson, USA.
Kelly L KarlageDepartment of Pharmacology, University of Arizona, Tucson, USA.
Catherine W MorgansDepartment of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, USA.
Sue A AicherDepartment of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, USA.
Tally M Largent-MilnesDepartment of Pharmacology, University of Arizona, Tucson, USA.

Funding

Mechanisms of Pain and Photophobia in Migraine and Dry EyeU01EY034680 · NEI · OREGON HEALTH & SCIENCE UNIVERSITY · PI SUE A AICHER, CATHERINE W MORGANS · 2022 to 2026
$4.5M
Targeting the Endocannabinoid System for Headache InterventionR01NS126752 · NINDS · UNIVERSITY OF ARIZONA · PI Tally Marie Milnes · 2023 to 2026
$2.4M
Primary Afferent Transmission in the Trigeminal Dorsal HornF32DE022499 · NIDCR · OREGON HEALTH & SCIENCE UNIVERSITY · PI MILNES, TALLY MARIE · 2011 to 2014
$127k
NEI NIH HHS U01 EY034680NIDCR NIH HHS F32 DE022499NINDS NIH HHS R01 NS126752
6 · The paper itself

Abstract

purposePhotophobia is a common and debilitating symptom associated with migraine. Women are disproportionately affected by migraines, with a higher prevalence and more severe symptoms compared to men. This study investigated the effects of cortical spreading depression on light-aversive and dark-seeking behaviors in a rat model, with an emphasis on sex differences.

methodExperiments were conducted on seven to eight-week-old male and female Sprague Dawley rats. cortical spreading depression was modeled by injections of potassium chloride or artificial cerebrospinal fluid into the occipital cortex through a guide cannula. Key behavioral assessments included light-aversive and dark-seeking behaviors measured using a three-chamber box, pupil to iris ratio, periorbital tightening, periorbital allodynia and facial withdrawal thresholds.

resultsOur results demonstrated that cortical potassium chloride injections significantly increased photophobic behaviors, particularly in female rats. Specifically, potassium chloride-injected females demonstrated a significant reduction in the time spent in the light chamber (p = 0.001) and increased time in the dark chamber compared to control rats (p = 0.01), indicating heightened light-aversion. Females exhibited more substantial pupil constriction and eyelid closure at 180 min after potassium chloride injection compared to artificial cerebrospinal fluid injection, suggesting a stronger physiological response to light. Similarly, a greater percent of female rats displayed periorbital allodynia (withdrawal threshold <6 g) over a post injection time course compared to male rats. Among rats that exhibited periorbital allodynia at least two consecutive time points, females had significantly lower facial withdrawal thresholds than males at 60-, 90-, 120-, and 180-min post injection (p < 0.05), suggesting a difference in magnitude and duration. Furthermore, the area under the curve for the time course experiment indicated development of tactile allodynia in periorbital region among female rats (p < 0.0001).

conclusionAltogether these findings highlight the importance of considering sex-specific differences in developing therapeutic strategies for the treatment of migraine. We report for the first time a complete time course analysis of migraine-related responses, providing a comprehensive overview of the dynamics involved. The results suggest that potassium chloride-induced cortical spreading depression may offer a valuable model for studying the underlying mechanisms and sex differences of photophobia in migraine, aiding in the development of targeted treatments.

Indexed as

Cortical Spreading DepressionPhotophobiaRats, Sprague-DawleySex CharacteristicsAnimalsBehavior, AnimalFemaleMalePotassium ChlorideRatsPotassium Chlorideallodyniagendermigraine with aurapain behaviorphotophobiarodent

Identifiers

PMID39782672
PMCPMC12593245

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LicenceCC BY-NC
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Registered trials

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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.