Objective To study the antioxidant properties of Capparis spinosa (C. spinosa) honey and propolis and the effect of combined honey and propolis administration on urine volume and electrolytes in rats. Methods C. spinosa honey [1 000 mg/kg body weight (b.wt)], propolis (100 mg/kg b.wt), honey/propolis mixture (C. spinosa honey 1 000 mg/kg b.wt/ propolis extract 100 mg/kg b.wt), distilled water (1 mL/kg b.wt) and furosemide (10 mg/kg b.wt) were orally administered to five groups of rats for 21 d. Urine volume, blood and urine sodium, potassium and chloride were measured. The antioxidant activity of propolis and honey was assessed and their total phenols and flavonoids were determined. Results Propolis and C. spinosa honey contain polyphenols including flavonoids and propolis demonstrated higher antioxidant activities than honey. Honey significantly increased urine volume and urine electrolyte excretion. Propolis had no significant effect on urine volume, but co-administration of propolis and honey caused significant diuresis. No major changes were observed in plasma electrolytes with the use of honey, propolis or their combination. Conclusions Honey and propolis have antioxidant activity and contain polyphenols including flavonoids that are more pronounced in propolis. Honey has a significant diuretic activity alone or in combination with propolis. This is the first study comparing the diuretic effect of co-administration of propolis and C. spinosa honey with furosemide.

Objective To investigate the diuretic, hypotensive and renal effect of Opuntia ficus-indica in two different species in oral and intravenous administration. Methods Diuretic activity was evaluated in rats with the plant cladode gel and aqueous extract administrated orally, and was evaluated in rabbits with plant extract administered intravenously. Single and repeated doses of cladode gel or aqueous extract of cladode were tested. Urine volume and blood and urine creatinine, sodium and potassium were measured, and creatinine clearance was calculated. The hypotensive effect of lyophilized extract of cladode was evaluated in rabbits. Two polyethylene PE50 catheters were used: one in the jugular vein for the infusion of the plant extract and the other in the carotid for the evaluation of the arterial pressure. Results The cladode gel or aqueous extract increased urine volume, creatinine clearance and urinary excretion of sodium and potassium without significant effect on serum creatinine or blood urea. Furosemide, gel and aqueous extract of cladode insignificantly lowered plasma potassium in rats. Intravenous administration of the lyophilized extract caused a significant decrease in mean arterial pressure in rabbits with a significant increase in urine volume and urine sodium and potassium; the effect was dose dependent. Intravenous administration of lyophilized extract did not affect plasma sodium or potassium. Conclusions Gel and aqueous extract of Opuntia ficus-indica cladode have a significant diuretic effect on rats, and the lyophilized extract has a diuretic and hypotensive effect on normotensive rabbits without deterioration in renal function test. Additional studies on active ingredients are essential to pave the way for clinical studies on diuretic and hypotensive effect of the plant.