Diuretic Vs toxic effects of Aerva lanata (Polpala) on kidney of Sprague Dawley rats

Abstract

Experimental studies were carried out in two phases to evaluate diuretic effect of the herb using hydrated rat assay technique and to determine possible toxic effects of prolonged use of Aerva lanata on the urinary tract of rats. Phase I – Two different concentrations of extract prepared using fresh and dried forms Aerva lanata was administered orally to 24 healthy rats. Findings of test groups were compared with those from rats administered water (negative control) and frusemide (positive control). Phase II – Two different concentrations of dried infusion of Aerva lanata was administered orally to 40 healthy rats for 30 days as per the WHO guidelines. Control group of rats were given water. Creatinine clearance (Ccr) and urine flow rate (UFR) were calculated to determine the effect of the herb on renal function. Kidneys, bladders and ureters were harvested for light (LM) and electron microscopic (EM) studies. Crude aqueous plant extract showed a diuretic activity. Ccr and UFR of test groups were not statistically different when compared with that of control group. LM of kidneys, ureters and bladders were negative for toxic changes. EM of kidneys showed significant changes in proximal convoluted tubular epithelial cells of rats in test groups. EM changes indicate that long term use produces structural changes.