抄録
Background
Ischemia reperfusion (I/R) injury is one of the main difficulties that arise from some surgical operations such as nephrectomy, aortic aneurysm damage. A decrease in blood flow and oxygen deficiency (ischemia phase) cause destruction of energy substrates. In spite of is essential to cell viability, reperfusion generates the formation of reactive oxygen species(ROS) leading to denervation of the ischemic bladder. Riboflavin (Rb) have been considered to be protective on lung, liver and heart ischemia reperfusion injury through the antioxidant properties.The aim of the present study was to evaluate the protective effects of riboflavin (Rb) in I/R injury in the rat bladder.
Methods
Thirty-two Sprague-Dawley female rats were divided into four groups. Sham-operated Control (C); I/R group; I/R and Rb treatment 25mg/kg (I/R+Rb p.o); I/R and N-acetylsystein treatment 100 mg/kg (I/R+NAC p.o). To induce ischemia the abdominal aorta was occluded for 60 min and then allowed 60 min of reperfusion. In the C group, the abdominal aorta was left intact and the animals were treated with saline. At the end of the reperfusion period, rats were decapitated to obtain bladder tissue samples for in vitro organ bath experiments, biochemical analyses and histological examination. The contractile responses to carbachol (CCh;10-8;10-4 mol/l) and relaxing responses to isoproterenol (ISO-10-8;10-4 mol/l) were cumulatively obtained. Biochemical assays such as malondialdehyde (MDA) levels, glutathione (GSH) levels; myeloperoxidase (MPO) activity and caspase-3 activity.
Results
In the I/R group increased MDA levels, MPO and caspase-3 activities and decreased GSH levels in the I/R group were reduced by Rb. On the other hand, in the I/R group, the isometric contractile responses of the bladder strips to CCh were lower than those of the control group and were reversed by treatment with both Rb and NAC. Otherwise, there were significant differences in relaxation induced by isoproterenol among the all groups.
Conclusion
Our findings indicate that ROS formation may play an important role in the pathogenesis of bladder I/R injury. Rb has antioxidant proporties that can protect against contractilite bladder dysfunctions.
