The Effect of Intestinal
Ischemia Duration on Changes in Plasma Antioxidant Defense
Status in Rats
H. ČÍŽOVÁ, A. LOJEK, L. KUBALA, M. ČÍŽ
Institute of Biophysics, Academy of Sciences of the Czech
Republic, Brno, Czech Republic
Received May 15, 2003
Accepted November 3, 2003
Summary
The purpose of this study was to follow up the changes in
antioxidative adaptive mechanisms induced by various periods of
small intestinal ischemia in Wistar rats. The superior
mesenteric artery was occluded for 15, 30, 45, 60 and 90 min.
After the respective ischemic intervals, a reperfusion was set
for 120 min. Samples of the serum and intestinal mucosa were
taken at the end of ischemia or at the end of reperfusion. Total
radical-trapping antioxidant parameter (TRAP) of the serum and
the oxidative burst of neutrophils were evaluated using
luminol-enhanced chemiluminescence. Individual antioxidants in
the serum and the concentration of thiobarbituric acid reactive
substances (TBARs) in both serum and intestinal mucosa were
measured spectrophotometrically. Increased activation of
circulating neutrophils was found after the reperfusion
irrespective of the duration of ischemia. TRAP of the serum was
increased at the end of the ischemia lasting from 30 to 90 min.
This effect was further enhanced by the subsequent reperfusion
period. Ascorbate and urate contributed considerably to the TRAP
value especially after reperfusion following 60 and 90 min of
ischemia. On the other hand, no significant changes in albumin
and bilirubin serum concentrations were observed. Contrary to
the mobilized antioxidative mechanisms, increased lipid
peroxidation was observed in both serum and mucosa samples.
Key words
Antioxidants • Small intestine • Ischemia • Reactive oxygen
species • Reperfusion
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