Diuretic Activities of Root Bark Aqueous and Ethanolic Extracts of Parquetina nigrescens: I-Effects on Urinary Excretion in Wistar Rat

Abstract

Background and objective: The root bark of Parquetina nigrescens is used in traditional medicine in the treatment of hypertension and edema for its diuretic properties. This study was conducted to examine the effects of this medicinal plant on the excreted urinary volume and contribute to scientific knowledge on its diuretic action. Methods: Water-overloaded rats were treated separately with increasing doses (5-70 mg/kg) of Parquetina nigrescens root bark aqueous and ethanolic 70 % extracts of and furosemide (FURO) at 5 mg/kg. Excreted urine was collected and measured. Results: Plant extracts caused increased urine excretion in rats. PNea 15 mg/kg and PNee 25 mg/kg were the most active doses. They caused an increase of volume of urine comparable to that induced by FURO 5 mg/kg. A very significant elimination of water overload at p < 0.001 was observed. And the recorded values were 42.73 ± 0.26% (PNea 15 mg/kg), 45.39 ± 0.190% (PNee 25 mg/kg) and 73.6 ± 0.24% (FURO 5 mg/kg) against 29.73 ± 0.24% (Saline solution NaCl 0.9%). Conclusion and perspectives: Increase of urine volume excreted induced by the extracts partly confirms the diuretic virtue of Parquetina nigrescens justifying its empirical use to treat hypertension and edema. However, these results, on their own, do not make it possible to elucidate the mechanism underlying diuretic activity of this plant. Additional studies should be carried out for this purpose.
 Keywords: Diuretic activity, urinary excretion volume, Parquetina nigrescens, Furosemide