The protective effect of rabbit serum paraoxonase-1 on the renal injury induced by dichlorvos in rats

Abstract

Objective To assess the protective effect of rabbit serum paraoxonase-1 (PON-1) on renal injury induced by dichlorvos in rats. Methods Totally 30 healthy S-D rats were randomly divided into 5 groups : control group ( group A, n=6), exposure group ( group B, n=6), PON-1 pretreatment group (group C, n=6), traditional atropine, pralidoxime treatment group(group D, n=6) and combination therapy group (group E, n=6). The rats of group A were given normal saline in equal volume of dichlorvos injected into abdominal cavity to make a false model of dichlorvos poisoning. In rats of groups B, C, D and E, 9 mg/kg dichlorvos was administered. In rats of groups C and E, PON-1 4 500 units/kg was injected into vein of the tails half an hour before dichlorvos administration. After dichlorvos exposure, rats in group D and E were treated with 45 mg/kg iodoprofen and 10 mg/kg atropine by intraperitoneal injection. The activity of blood urea nitrogen (BUN) was assayed with urease. Serum creatinine (Cr) were measured by picric acid colorimetry. Serum Cys-C, KIM-1 and NAG in urine were determined by ELISA. Ultrastructural changes in renal tissues of rats were examined by light microscopy. The differences in laboratory findings between groups were compared. Results The creatinine level in group B was significantly higher than that in other groups (P<0.05). The levels of Cys-C, KIM-1 and NAG in group B and group D were significantly higher than those in group A (P<0.01). But there were no significant differences in above biomarkers among group C, group E and group A. There were no significant differences in above biomarkers between group B and group D. In group B, inflammatory cells infiltrated extensively in renal tissues and, the renal cells were congested and edematous, the lumen was obliterated and the border of the brush disappeared. The tubular structures were not clearly distinct found in group B, but edema and inflammatory cell infiltration with lesser degree were found in group D than those in dichlorvos exposure groups. The clearly distinct structure of the tube without completely occluded lumen in group D, and the most serious lesions were found in distal convoluted tubules. In group C, and group E, there were only mild congestion and edema without significant cell degeneration and necrosis. In group A, the structure of renal tubular epithelium was clearly distinct with brush-shaped margin, and without tubular or necrotic cell debris in the lumen. Conclusion The rabbit serum PON-1 can protect the renal tissue of rats after dichlorvos exposure. Key words: Dichlorvos; Paraoxonase -1; Renal injury; Protective effect; Rats