M Rajabi Pour - MSc, Department of Radiology, School of Paramedicine, Shiraz University of Medical Sciences, Shiraz, Iran
R Fardid - PhD, Ionizing and Non-ionizing radiation protection research center, School of Paramedicine, Shiraz University of Medical, Sciences, Shiraz, Iran
T Zare - PhD Student, Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
F Kargar Shouroki - PhD, Occupational Health Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
M A Mosleh-Shirazi - PhD, Ionizing and Non-ionizing radiation protection research center, School of Paramedicine, Shiraz University of Medical, Sciences, Shiraz, Iran
A Behzad Behbahani - PhD, Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedicine, Shiraz University of Medical Sciences, Shiraz, Iran

Background: Some operating room personnel are occupationally exposed to genotoxic agents such as anesthetic gases and ionizing radiation. Adaptive response, as a defense mechanism, will occur when cells become exposed to a low dose of factors harming DNA (priming dose), which in the subsequent exposure to higher dose of those factors (challenging dose), show more resistance and sensibility.. Objective: The aim of this study was to investigate adaptive response or synergy of ionizing radiation in the operating room personnel exposed to anesthetic gases by evaluation of the relative gene expression changes of effective genes for DNA repair such as Ku۸۰, Ligase۱ and P۵۳.Material and Methods: In this case-control study, ۲۰ operating room personnel and ۲۰ nurses (who were not present in the operating room) as controls were studied. Venous blood samples were drawn from participants. In order to evaluate the adaptive response, a challenging dose of ۲Gy gamma radiation was applied to blood samples. Moreover, RNA extraction and cDNA synthesis were performed. Gene expression level was studied by RT-qPCR and compared with the control group. Results: : Ligase۱ and P۵۳ expression in the operating room personnel was significantly higher than that of the control group before irradiation (P˂۰.۰۰۱). Statistically, there was no significant difference in the Ku۸۰ and P۵۳ expression in the operating room personnel before and after irradiation. Conclusion: Given the findings of this study, exposure to challenging dose of gamma radiation can induce adaptive response in expression of Ku۸۰ and P۵۳ genes in operating room personnel.

Adaptive response, Ionizing radiation, Anesthetic Gases, Operating Room Personnel, Occupational Exposure, DNA Repair, Gene expression, RT-qPCR