Increased nociceptive sensitivity is associated with periodontal inflammation and expression of chronic pain genes in gingival tissues of male rats

Abstract

bjective: This study aimed to evaluate the inflammatory response, hyperpolarization-activated cyclic nucleotidegated 2 (HCN2), and voltage-gated potassium (Kv) 9.1 channel expression in rats with paclitaxel-induced neuropathic pain-like behavior. Methods: Sixteen male Sprague Dawley rats were divided equally into two groups: control and paclitaxel-induced pain (PTX). The attachment loss and inflammatory cell infiltrate levels were analyzed histometrically and immunohistochemically. The gene expression of HCN2 and KCNS1 was analyzed by qPCR in the brain and gingival tissues. Results: The attachment loss and prominent infiltration of inflammatory cells were significantly higher in the PTX group than in the control groups. In gingival tissues; the expression levels of HCN2 (p = 0,0011) were significantly higher and KCNS1 (p = 0,0003) were significantly lower in the PTX group than in the control groups. Conclusion: Increased nociceptive sensitivity, may play a role in periodontal inflammation. KCNS1 may decrease and HCN2 expression may increase in periodontium in permanent chronic pain states. The results of the present study may be helpful in developing new approaches to alleviate pain and maintain periodontal health in patients suffering from orofacial pain.