Format

Send to

Choose Destination
Pain. 2018 Mar;159(3):540-549. doi: 10.1097/j.pain.0000000000001124.

Induction of chronic migraine phenotypes in a rat model after environmental irritant exposure.

Author information

1
Departments of Biochemistry and Molecular Biology.
2
Anatomy and Cell Biology and.
3
Pharmacology and Toxicology, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, USA.

Abstract

Air pollution is linked to increased emergency department visits for headache and migraine patients frequently cite chemicals or odors as headache triggers, but the association between air pollutants and headache is not well understood. We previously reported that chronic environmental irritant exposure sensitizes the trigeminovascular system response to nasal administration of environmental irritants. Here, we examine whether chronic environmental irritant exposure induces migraine behavioral phenotypes. Male rats were exposed to acrolein, a transient receptor potential channel ankyrin-1 (TRPA1) agonist, or room air by inhalation for 4 days before meningeal blood flow measurements, periorbital cutaneous sensory testing, or other behavioral testing. Touch-induced c-Fos expression in trigeminal nucleus caudalis was compared in animals exposed to room air or acrolein. Spontaneous behavior and olfactory discrimination was examined in open-field testing. Acrolein inhalation exposure produced long-lasting potentiation of blood flow responses to a subsequent TRPA1 agonist and sensitized cutaneous responses to mechanical stimulation. C-Fos expression in response to touch was increased in trigeminal nucleus caudalis in animals exposed to acrolein compared with room air. Spontaneous activity in an open-field and scent preference behavior was different in acrolein-exposed compared with room air-exposed animals. Sumatriptan, an acute migraine treatment blocked acute blood flow changes in response to TRPA1 or transient receptor potential vanilloid receptor-1 agonists. Pretreatment with valproic acid, a prophylactic migraine treatment, attenuated the enhanced blood flow responses observed after acrolein inhalation exposures. Environmental irritant exposure yields an animal model of chronic migraine in which to study mechanisms for enhanced headache susceptibility after chemical exposure.

PMID:
29200178
PMCID:
PMC5812801
DOI:
10.1097/j.pain.0000000000001124
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wolters Kluwer Icon for PubMed Central
Loading ...
Support Center