High dose of QX-314 produces anti-nociceptive effect without capsaicin in rats with inflammatory TMJ pain.
- Author:
Kui Ye YANG
1
;
Min Su KIM
;
Eun Kyung KIM
;
Mi Sun KONG
;
Jong Soo AHN
;
Jong Hun LEE
;
Jin Sook JU
;
Dong Kuk AHN
Author Information
1. Department of Oral physiology, School of Dentistry, Kyungpook National University, Daegu (700-412), Korea. dkahn@knu.ac.kr
- Publication Type:Original Article
- Keywords:
QX-314;
TMJ pain;
Capsaicin;
Capsazepine;
formalin test
- MeSH:
Anesthesia;
Animals;
Capsaicin*;
Formaldehyde;
Humans;
Male;
Pain Measurement;
Rats*;
Rats, Sprague-Dawley;
Temporomandibular Joint*
- From:International Journal of Oral Biology
2013;38(4):135-140
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
The present study investigated the effects of QX-314 on inflammatory pain of the temporomandibular joint (TMJ). Experiments were carried out on male Sprague-Dawley rats weighing 220-280 g. Under anesthesia, the TMJ of each animal was injected with 50 microL of formalin (5%). The number of noxious behavioral responses, including rubbing or scratching of the facial region including the TMJ area, was recorded over 9 sequential 5 min intervals for each animal. Although 2.5% QX-314 did not affect formalin-induced nociceptive behavior, administration of 5% QX-314 with formalin significantly decreased the number of scratches produced by the formalin injection. Co-administration of capsaicin, a TRPV1 agonist, with 2.5% QX-314 produced significant anti-nociceptive effects whereas 2.5% QX-314 alone did not. However, the co-administration of capsaicin did not enhance the anti-nociceptive effects in the 5% QX-314-treated rats. Moreover, the co-administration of capsazepine, a TRPV1 antagonist, did not attenuate anti-nociceptive effects in the 5% QX-314-treated rats. These findings suggest that TRPV1 is effective in the transport of low but not high doses of QX-314. Moreover, a high dose of QX-314, which is not mediated by peripheral TRPV1 activity, may be viable therapeutic strategy for inflammatory pain in the TMJ.