The Influencer Effect of Dexmedetomidine on Radioiodine Relevant to Lacrimal Gland Impairment Running Title: Dexmedetomidine on Radioionized Lacrimal Gland

Purpose: To assess the potential influencing effects of Dexmedetomidine (DEX) at impaired lacrimal glands after high-dose radioiodine treatment (RAI). Materials and methods Thirty-six rats were arbitrarily seperated into 3 groups; Sham, RAI and DEX group. DEX group were given DEX and RAI, Sham group were given same millimeters of saline and RAI group were given RAI only. All forms of lacrimal glands including harderian glands (HG), extraorbital (EG) and intraorbital (IG) lacrimal glands were evaluated for immunohistochemic, histopathologic assessments and also for tissue cytokines, oxidant and antioxidant levels. Results DEX significantly ameliorated histopathologic changes such as; periacinar fibrosis, acinar atrophy, lymphocytic infiltration, ductal proliferation, lipofuscin-like accumulation, and nucleus changes caused by RAI in all lacrimal gland forms ( p  < 0.05 for all of the parameters). However, periductal fibrosis was improved significantly only in EG (p = 0.049) and mast cell infiltration was improved significantly only in IG (p = 0.038) in DEX groups. There was a significant decrease in the elevated caspase-3 and TUNEL levels after RAI administration in the DEX group in all lacrimal gland forms ( p  < 0.05 for all parameters). DEX attenuated NF-kb, TNF-α, IL-6 levels and significantly diminished total oxidant status and raised total antioxidant status levels ( p  < 0.05 for all of the parameters). Conclusions The results of this study demonstrated that following RAI, DEX diminished inflammation, tissue cytokine levels and apoptosis and ameliorated impaired histopathologic pattern of the lacrimal glands.