Influence of orofacial pain, in superficial and deep tissue, on the anxiety levels in rats
Keywords:Orofacial pain, anxiety, rats, EPM
AbstractPurpose: The present study aimed to determine the influence of orofacial pain in superficial and deep tissue on anxiety levels in male Wistar rats. Methods: Orofacial pain was induced by injecting 50 μL of 1% formalin in the lip (superficial tissue) and in the temporomandibular joint (TMJ) (deep tissue) of male Wistar rats. The anxiety level was measured by the elevated plus maze (EPM) test. The standard measures (number of entries into open and enclosed arms, and time spent in opened ones), were recorded. The three measures of plus-maze behavior calculated were the percentage of entries into the open arms (% EOA) (100 X open/total), the percentage of time spent in the open arms (% TSOA) (100 X open/total) and the number of entries into the closed arms (NECA). Data were analyzed with ANOVA and Tukey’s tests. Results: The formalin injection in the lip and in the TMJ region significantly increased the anxiety level as measured by the percentage of time spent inside and the number of entries in the open arms of the EPM test, but did not increase the general activity measured by the number of entrances in the closed and opened arms. Anxiety response was significantly reduced by Diazepam® administration (1 mg/kg) before the formalin injection to lip/TMJ. Conclusion: The results suggest that the orofacial nociceptive response induced by the injection of 1% formalin in the lip or TMJ region increases the anxiety level in rats and that Diazepam® can reduce it.
The submission of originals to Odonto Ciência implies the transfer by the authors of the right for publication. Authors retain copyright and grant the journal right of first publication. If the authors wish to include the same data into another publication, they must cite Odonto Ciência as the site of original publication.
CREATIVE COMMONS LICENSE
As this journal is open access, the articles are allowed free use in scientific and educational applications, with citation of the source.
According to the type of Creative Commons License (CC-BY 4.0) adopted by Odonto Ciência, the user must respect the requirements below.
You are free to:
Share — copy and redistribute the material in any medium or format.
Adapt — remix, transform, and build upon the material for any purpose, even commercially.
However, only under the following terms:
Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests Odonto Ciência endorses you or your use.
No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.
You do not have to comply with the license for elements of the material in the public domain or where your use is permitted by an applicable exception or limitation.
No warranties are given. The license may not give you all of the permissions necessary for your intended use. For example, other rights such as publicity, privacy, or moral rights may limit how you use the material.
For more details on the Creative Commons license, please follow the link in the footer of this website.