Purpose: To investigate whether free radical metabolism is changed due to i
soflurane treatment and, if so, to elucidate the role of changed free radic
al metabolism in the nephrotoxicity.
Materials and methods: Fifteen guinea pigs were used in the study. Five wer
e treated with isoflurane in oxy gen, five with oxygen and five were contro
ls. Animals were exposed to isoflurane and oxygen three limes. Each treatme
nt was performed for 30 min once a day for three consecutive days. Activiti
es of free radical enzymes, superoxide dismutase (SOD), catalase (CAT), and
glutathione peroxidase (GSH-Px); values of antioxidant parameters, antioxi
dant potential (AOP), non-enzymatic superoxide radical scavenger activity (
NSSA) and oxidation resistance (OR) and, level of an oxidant parameter name
ly, malondialdehyde (MDA) were determined in the renal tissues of the group
s. Blood was also obtained for serum creatinine and urea analyses.
Results: AOP, NSSA, SOD and CAT activities were decreased; (0.0188 +/- 0.00
26 vs 0.0156 +/- 0.0015, P < 0.025; 8.72 +/- 1.80 vs 6.40 +/- 1.22, P < 0.0
5; 76.71 +/-. 18.54 vs 52.79 +/- 11.68, P < 0.025; 71.26 +/- 15.58 vs 55.39
+/- 8.83; P < 0.05, respectively) but, MDA level, OR value and GSH-Px acti
vities increased (10.89 +/- 1.57 vs 15.87 +/- 2.97, P < 0.01; 0.84 +/- 0.34
vs 2.28 +/- 1.39, P < 0.05; 1.45 +/- 0.83 vs 3.45 +/- 1.20, P < 0.01, resp
ectively) in kidney tissues from isoflurane-treated group compared with con
trols, No differences were observed between control and oxygen groups with
regard to all analysis parameters except GSH-Px.
Conclusion: Isoflurane impairs the antioxidant defence system and this oxid
ant stress may play a part in the isoflurane-induced renal toxicity.