Histological and immunohistochemical study of the postulated protective effect of L-arginine on glycerol induced acute renal failure in adult male albino rats

ABSTRACT

L-arginine, a semi essential amino acid, is the main source for the generation of nitric oxide via nitric oxide synthase. Nitric oxide plays a crucial role in the pathogenesis of acute renal failure. This study aimed to investigate if L-Arginine has a protective role in glycerol induced renal failure in rats. Forty adult male albino rats were randomly allocated into four equal groups. Group I [Control 1] The rats were intramuscularly injected with a single dose of saline solution. Group II [Control 2] L-arginine was once given through nasal gastric tube [125 mg/kg body weight]. Group Ill Acute renal failure was induced by single intramuscular injection of 50% glycerol [10 ml/kg body weight]. Group IV L-arginine was given as in group II an hour before glycerol which was injected similarly to group III. Eighteen hours after the end of treatment in each group, blood samples were extracted for estimation of renal functions. Kidneys were removed and used for light and transmission electron microscopical studies. For light microscopic purpose, paraffin sections were stained with Hematoxylin and Eosin, Periodic Acid Schiff and immunohistochemically for tissue inducible nitric oxide. Using image analyzer, quantitative measurements and analysis of the optical densities for Periodic Acid Schiff and inducible nitric oxide positive reactions were done. One-way ANOVA followed by Dunnett's test and Chi square test were used to determine the significance between the groups. Glycerol in group III led to deterioration of renal functions; degeneration, necrosis, sloughed brush borders, increased inducible nitric oxide staining density, dense nuclei and small atrophic mitochondria of the proximal convoluted tubules, thickness of foot processes, distorted and thickened glomerular basal lamina, as well as swollen glomerular capillaries endothelial cells with electron dense deposition. These changes were markedly reduced by using L-arginine in group IV. The findings implied that L-arginine plays an important role in protection against glycerol induced acute renal failure