Diuretic activity assessment of an aqueous extract of Hibiscus sabdariffa (Malvaceae) leaves on Wistar rats

Hibiscus sabdariffa (Malvaceae) is a plant known as a diuretic. We undertook to evaluate the therapeutic effectiveness of this plant. Twenty Wistar rats aged between 6 and 8 weeks and weighing between 150 and 250 g were divided into five homogeneous batches of four rats. Batch 1 received only the saline overload, NaCl (50 ml/kg). Immediately after the saline overload, batches 2, 3, 4 and 5 received orally, furosemide, the standard diuretic (40 mg/kg bw), or single doses of 500, 1000 and 1500 mg/kg bw of the aqueous extract of H. sabdariffa leaves, respectively. The results showed that, 24 hours after the administrations, the urinary volumetric excretions of 123.06±11.07; 66.11± 6.19; 112.22±4.36 and 61.39±10.28% respectively. The increases in urinary volumetric excretion induced by the extract were statistically significant compared to the control rats (34.99±8.46%). The extract at a dose of 1000 mg/kg bw and furosemide showed statistically similar values of urinary volumetric excretion. This urinary excretion was accompanied by an elimination of Na+ and K+ ions similar to furosemide. The urinary measurement of creatinine and urea also revealed that the extract did not interfere with normal renal function during treatment. This study shows that the aqueous extract of H. sabdariffa leaves has diuretic and natriuretic activity similar to that of furosemide. This activity could be attributed to the presence of alkaloids, steroids and flavonoids, compounds known for their diuretic effects. Keywords: Hibiscus sabdariffa, Furosemide, urinary excretion, diuretic