Diuretic activity of aqueous extract of Nigella sativa in albino rats

The study aims to evaluate the diuretic effect and acute toxicity of a crude aqueous extract of Nigella sativa using animal models. To evaluate the diuretic activity of the plant, Albino rats were divided into five groups. The control group received normal saline (10 mL/kg), the reference group received furosemide (10 mg/kg) and the test groups were administered different doses (i.e., 10, 30 and 50 mg/kg) of the crude extract by intra-peritoneal route, respectively. Graph Pad Prism was used for the statistical analysis and p-values less than 0.05 were considered statistically significant. We observed significant diuretic, kaliuretic and natriuretic effects in the treated groups in a dose dependent manner. However, urinary pH remained unchanged during the course of the study. The diuretic index values showed good diuretic activity of the crude extract. The Lipschitz values demonstrated that the crude extract, at the dose of 50 mg/kg, showed 46% diuretic activity compared with furosemide. With regard to the acute toxicity study, no lethal effects were observed among Albino mice even at the higher dose of 5000 mg/kg. The extract of Nigella sativa, at the dose of 50 mg/kg, significantly increased the urinary volume and modified the concentration of urinary electrolytes, and there was observed no signs of acute toxicity associated with the crude extract. Further studies are encouraged to isolate the pure phytochemical responsible for diuresis.