This study was aimed to evaluate the effect of methanol extract of Napoleonae imperialis leaves against methotrexate renal damage in albino rats. Thirty (30) male albino rats of mean weight 130 g were used for this study. The animals for the study were grouped into five (5) of six (6) rats each. Group A (normal control) received feed and water only and Group B (positive control) was induced with methotrexate without treatment. Test groups (C and D) were orally given 250 mg and 500 mg/kg b.wt of leaves extract, and group E was orally given the extract only (500 mg/kg b.wt) respectively for 14 days. All the rats used in this study were initially subjected to renal damage using 0.5 ml/kg of methotrexate except the normal control group and the group that received the extract only. The rats were sacrificed after 14 days and the blood samples were collected for biochemical analysis, From the result obtained, there was a significant (p< 0.05) decrease in the test groups that received 250 mg/kg and 500 mg/kg b.wt of the plant extract in (Urea, Creatinine and Na+ ), and a significant increase (p< 0.05) in  K+ and Cl-. Also there was a significant (p< 0.05) decrease in (Urea, Creatinine, and Na+) in comparison with the control groups and the group that received the extract only (500 mg/kg b.wt), and a significant increase (p< 0.05) in (K+ and Na+). The results of this study indicate that the methanol extract of Napoleonae imperialis leaves may have exerted renal functioning effects in albino rats, and may also be used pharmacologically in the management of organ toxicity.

Keywords: Creatinine, Urea, Renal damage, Methotrexate, and Sodium ion.