Molecular and Cellular Biochemistry 294: 31–36, 2007. DOI: 10.1007/s11010-006-9207-6 c ❣ Springer Effects of repeated desﬂurane and sevoﬂurane anesthesia on enzymatic free radical scavanger system Bayazit Dikmen, 1 Yusuf Unal, 2 H. Kutluk Pampal, 2 Nilhan Nurlu, 3 Omer Kurtipek, 2 Orhan Canbolat, 3 Candan ¨ Ozo˘ gul 4 and Mustafa Kavutcu 3 1 Ankara Numune Hospital, Department of Anesthesiology & Reanimation, Gazi University Medical Faculty, 2 Department of Anesthesiology & Reanimation, 3 Medical Biochemistry Department and 4 Department of Histology and Embriology, 06510-Bes ¸evler, Ankara, Turkiye Received 10 March 2006; accepted 28 March 2006; Published online: 29 November 2006 Abstract Background: To investigate the possible effects of repeated sevoﬂurane and desﬂurane anesthesia on hepatocellular system by evaluating the free radical metabolism, hepatocellular enzymes and histopatholgical changes in rats. Methods: Four groups of animals were studied. Sevoﬂurane 2% (v/v) and desﬂurane 6% (v/v) in air/O 2 were administered to animals in group II (n = 9) and III (n = 9) respectively. 100% (v/v) O 2 was administered in group IV (n = 9). Administration was done for 60 minutes over 3 days. Nine animals were allocated to control group (group I), superoxide dismutase (SOD), catalase (CAT), glutathion peroxidase (GSH-Px), glutathione-s-transferase (GST) and thiobarbituric acid reactive substances (TBARS) were studied. Also electron microscopy was performed. Results: Catalase, SOD, GSH-Px, GST activities and TBARS levels were signiﬁcantly higher in groups II and III than in group I ( p < 0.05). All parameters were signiﬁcantly higher in groups II versus group IV ( p < 0.05). On the other hand, SOD, GSH-Px and GST activities were signiﬁcantly elevated in group III than IV, but CAT activity and TBARS levels were not signiﬁcantly. Catalase, SOD, GSH-Px, GST but not TBARS levels were signiﬁcantly higher in groups II and III than in group IV ( p < 0.05). TBARS levels were higher in group III than in group IV, but this elevation was not statistically signiﬁcant. CAT, SOD and GSH-Px activities were signiﬁcantly higher in groups II than in group III ( p < 0.05). Conclusion: Although electron microscopy ﬁndings were similar for group II and III, we can conclude that sevoﬂurane might cause more cellular damage than desﬂurane by causing higher activation of free radical metabolising enzymes. (Mol Cell Biochem 294: 31–36, 2007) Key words: free radicals, sevoﬂurane, desﬂurane, hepatotoxicity, glutathione-S-transferase, antioxidant enzymes Introduction It is a well-known fact that volatile anesthetic agents may cause hepatotoxicity [1–5]. Halogenated anesthetic agent hepatotoxicity, especially for halothane studied widely. Hy- persensitivity reactions, toxic metabolites, multiple expo- sure, duration of anaesthesia, hypoxia and obesity are the Address for offprints: M. Kavutcu, Gazi University Medical Faculty, Medical Biochemistry Department, 06510-Be¸ sevler/Ankara, Turkiye (E-mail: kavutcu@gazi.edu.tr) questioned factors for the possible mechanism of halothane hepatotoxicity [6]. Sevoﬂurane, desﬂurane and isoﬂurane are more preferred agents than halothane in recent years. Al- though halothane, isoﬂurane and desﬂurane are metabolised via cyt p-450 2E1 their rate of metabolism differs. However, sevoﬂurane is metabolised by a different mechanism than these three agents. Several studies investigating halothane 2006