Isoflurane impairs antioxidant defence system in guinea pig kidney.
OBJECTIVE
To investigate whether free radical metabolism is changed due to isoflurane treatment and, if so, to elucidate the role of changed free radical metabolism in the nephrotoxicity.


METHODS
Fifteen guinea pigs were used in the study. Five were treated with isoflurane in oxygen, five with oxygen and five were controls. Animals were exposed to isoflurane and oxygen three times. Each treatment was performed for 30 min once a day for three consecutive days. Activities of free radical enzymes, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px); values of antioxidant parameters, antioxidant potential (AOP), non-enzymatic superoxide radical scavenger activity (NSSA) and oxidation resistance (OR) and, level of an oxidant parameter namely, malondialdehyde (MDA) were determined in the renal tissues of the groups. Blood was also obtained for serum creatinine and urea analyses.


RESULTS
AOP, NSSA, SOD and CAT activities were decreased; (0.0188 +/- 0.0026 vs 0.0156 +/- 0.0015, P < 0.025; 8.72 +/- 1.80 vs 6.40 +/- 1.22, P < 0.05; 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 activities 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, respectively) in kidney tissues from isoflurane-treated group compared with controls. No differences were observed between control and oxygen groups with regard to all analysis parameters except GSH-Px.


CONCLUSIONS
Isoflurane impairs the antioxidant defence system and this oxidant stress may play a part in the isoflurane-induced renal toxicity.
Durak
I
I
Department of Biochemistry, Medical Faculty, Ankara University, Turkey. durak@pallas.dialup.ankara.edu.tr
Oztürk
H S
HS
Dikmen
B
B
Güven
C
C
Cimen
M Y
MY
Büyükkoçak
S
S
Kaçmaz
M
M
Avci
A
A
D018685:Anesthetics, Inhalation / Q000633:toxicity*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism; D005609:Free Radicals / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006168:Guinea Pigs; D007530:Isoflurane / Q000633:toxicity*; D007668:Kidney / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008315:Malondialdehyde / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
D018685:Anesthetics, Inhalation; D000975:Antioxidants; D016166:Free Radical Scavengers; D005609:Free Radicals; D008315:Malondialdehyde; D007530:Isoflurane; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase