Does the analysis based on a histological and immunohistochemical grading system in the model of BDL kidney allow the quantification of the degree of injury?

The aim of this study is to evaluate histopathological findings induced by Nomega-nitro-L-arginine methyl ester (L-NAME) and molsidomine (MOL) on the kidney of bile duct ligated rats. Forty Sprague-Dawley rats, each weighing 125 to 140 g, were included in the study. Extent of histological glomerular injury scores (GIS), arterial injury scores (AIS), and tubulointerstitial injury scores (TIS) in each animal were graded. Alpha-smooth muscle actin (alpha-SMA), tenascin, lectin (Ulex europaeus agglutinin-1), and vimentin were used to determine extent of the injury. The cholestasis was evidenced by a significant increase in the levels of serum total bilirubin in BDL rats (p < 0.01). Malondialdeyde MDA levels increased by the bile duct ligation (BDL) to 12.10 +/- 0.45. This value was significantly higher than the other groups (p < 0.01). Changes in the BDL kidney were marked at 7 days after surgery. GIS were observed to have the highest score, especially at juxtamedullary region in BDL/L-NAME rats, and AIS were also the highest score in this region. These observations were lower in BDL/MOL rats. There is a correlation between GIS and AIS scores (r = .2, p < .01). TIS revealed that BDL/L-NAME rats were significantly more damage than rats in the other groups (p<.001). MOL-treated rats showed considerably fewer lesions in the tubules and interstitium (p < .001). The tubular injuries observed in BDL and BDL/L-NAME rats were significantly attenuated by MOL treatment. Lectin was more and extensively stained in tubular epithelia of the BDL/L-NAME group than in the other (p <.05). Expression of tenascin in tubular epithelia was significantly higher in BDL and BDL/L-NAME as compared with controls (p < .01). Fibrous tissue was only observed in the BDL and BDL/L-NAME group. These areas were weakly stained with vimentin. alpha-SMA staining was more reduced in the L-NAME-treated arterioles than in BDL/MOL (p < .05). In conclusion, the analysis of cell injury based on a histological grading system in the model of BDL kidney allows the quantification of the degree of injury.