EN
The study was performed on 16 albino Wistar female rats divided into two equal groups: experimental and control. The rats from the experimental group received per os, every second day for 2 weeks 40 mg/kg b.w. of L-arginine. The rats from the control group received, in the same manner, 2 ml of distilled water. The animals were decapitated after 3 weeks of the experiment. After decapitation specimens from the kidneys were collected, fixed in 10% formalin, and then embedded in paraffin blocks. Protein caspase 3 was detected using the standard three step immunohistochemical method. Additionally, the apoptotic index was evaluated. The study shows that L-arginine, as a donor of exogenous nitric oxide, induced the apoptotic signal in normal renal tubular cells of the rats. The apoptotic index statistically significantly increased in the epithelial cells of the treated renal tubules compared to the control. The immunohistochemical reaction for the executing caspase 3 in the renal tubular cells, although increased in comparison with the control, was statistically insignificant.