Evidence map›Paper›PMID 41239208›Full record

ArticleThe journal of headache and pain2025

Tear fluid CGRP rises during glyceryl trinitrate-induced headache in migraine patients.

Katharina Kamm, Marie-Christine Khorsandian, Andreas Straube, Ruth Ruscheweyh

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Article in The journal of headache and pain, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

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3citing papers in PubMed
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3 citing papers in PubMed.

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5 · Who and what money

Authors and funding

4 authors.

Katharina KammDepartment of Neurology, University Hospital, LMU Munich, Munich, Germany. katharina.kamm@med.uni-muenchen.de.
Marie-Christine KhorsandianDepartment of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
Andreas StraubeDepartment of Neurology, University Hospital, LMU Munich, Munich, Germany.
Ruth RuscheweyhDepartment of Neurology, University Hospital, LMU Munich, Munich, Germany.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundCalcitonin gene-related peptide (CGRP) plays an important role in migraine pathophysiology and is a marker of trigeminal activity. We investigated tear fluid CGRP levels interictally and ictally using the glyceryl trinitrate (GTN) experimental migraine model.

methodsStudy participants were assessed interictally and during an experimental headache using GTN. Interictal tear fluid CGRP levels were assessed in episodic migraine (EM) patients and healthy controls (HC). At the day of experimental headache, tear fluid was sampled in EM patients before and after intravenous GTN application. Participants were free to use their usual abortive medication if needed. Tear fluid CGRP levels were analyzed using two different ELISAs.

results26 EM patients and 20 healthy controls were examined interictally. Interictal tear fluid CGRP was significantly higher in EM patients compared to HCs (Abbexa® CGRP ELISA: interictal EM patients: 2.78 ± 1.99 ng/ml, HC: 1.35 ± 0.78 ng/ml, U = -2.969, p = 0.003). 17 EM patients were analyzed after intravenous GTN. Tear fluid CGRP levels were significantly elevated at maximum headache compared to baseline (Abbexa® CGRP ELISA: 3.84 ± 1.96 ng/ml vs. 2.78 ± 2.38 ng/ml, p = 0.025; Cusabio® CGRP ELISA: 1.43 ± 0.96 ng/ml vs. 0.75 ± 0.77 ng/ml, p < 0.001). Seven patients developed a headache with an intensity ≥ 5 on the numerical rating scale (NRS) and showed a significantly higher rise in tear fluid CGRP compared to patients with a headache < 5 on the NRS (Abbexa® CGRP ELISA: + 2.11 ± 2.14 ng/ml vs. + 0.32 ± 1.33 ng/ml, p = 0.033; Cusabio® CGRP ELISA: + 1.45 ± 0.81 ng/ml vs. + 0.09 ± 0.53 ng/ml; p < 0.001). Tear fluid CGRP levels were significantly more reduced after intake of abortive medication than after spontaneous headache improvement (Abbexa® CGRP ELISA: -0.82 ± 1.26 ng/ml vs. 1.24 ± 2.06 ng/ml, p = 0.014; Cusabio® CGRP ELISA: -0.66 ± 1.27 ng/ml vs. -0.12 ± 0.24 ng/ml, p = 0.033).

conclusionThe present results demonstrate validity of tear fluid CGRP assessment during experimental migraine, detecting a rise of tear fluid CGRP levels during GTN-induced headache. The intake of abortive medication reduced tear fluid CGRP levels significantly more than spontaneous headache improvement.

Indexed as

Calcitonin Gene-Related PeptideMigraine DisordersNitroglycerinTearsAdultFemaleHumansMaleMiddle AgedVasodilator AgentsYoung AdultCalcitonin Gene-Related PeptideNitroglycerinVasodilator AgentsCGRPGTNHeadacheMigraineTear fluid

Identifiers

PMID41239208
PMCPMC12619329

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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.