Enzymatic antioxidant defence mechanism in rat intestinal tissue is changed after ischemia-reperfusion. Effects of an allopurinol plus antioxidant combination
M. Kacmaz et al., Enzymatic antioxidant defence mechanism in rat intestinal tissue is changed after ischemia-reperfusion. Effects of an allopurinol plus antioxidant combination, CAN J SURG, 42(6), 1999, pp. 427-431
OBJECTIVES: TO establish the antioxidant status of rat intestinal tissues a
fter ischemia-reperfusion and to determine if pretreatment with an allopuri
nol and antioxidant vitamin combination gives any protection against mucosa
l injury.
EXPERIMENTAL ANIMALS: Twenty rats were divided into 4 groups of 5 animals e
ach,
METHODS: Group 1 (control) rats were not subjected to ischemia-reperfusion
and received no allopurinol plus vitamin combination; group 2 rats received
vitamins C (200 mg/kg) and E (100 mg/kg) and allopurinol (50 mg/kg) combin
ation daily for 3 days prcoperatively; group 3 rats were subjected to ische
mia-reperfusion only; and group 4 rats were subjected to ischemia-reperfusi
on and received the vitamin and allopurinol combination.
MAIN OUTCOME MEASURES: Activities of superoxide dismutase (SOD), glutathion
e peroxidase (GSH-Px) and catalase (CAT) enzymes, the level of thiobarbitur
ic acid-reagent substances (TBARS) and histologic grading of tissue samples
,
RESULTS: SOD and GSH-Px activities were decreased, but-the CAT activity and
TBARS level increased. Pretreatment of the rats with the allopurinol-vitam
in C -vitamin E combination did not have any significant effect on the enzy
me activities. However, it resulted in important reductions in the TBARS ti
ssue levels. Histologic investigation revealed significant mucosal injury i
n group 3 rats compared with group 4 rats (mean [and standard deviation] fo
r grading, 4.6 [0.5] versus 1.8 [0.4]).
CONCLUSIONS: The enzymatic antioxidant defence system was significantly cha
nged after ischemia-reperfusion and intestinal tissue was exposed to increa
sed oxidant stress, the results of which were peroxidation of some cellular
structures and increased concentrations of oxidative: products, Although a
ntioxidant treatment did not drastically affect the enzyme activities or af
ford complete protection of cellular structures against deformation, it app
arently could eliminate oxygen radicals and prevent peroxidative reactions.