Effect of Equaisetum arvense L. aerial parts of ethanolic extract on prevention of calcium oxalate crystals in kidney of male Wistar rats

Urolithiasis is a worldwide problem, sparing no geographical, cultural, or racial groups. Kidney stones are composed of inorganic and organic crystals amalgamated with proteins. Crystallisation and subsequent lithogenesis can happen with many solutes in the urine. Calcareous stones are still by far the most common nephroliths accounting for more than 80% of stones. In Iranian folk medicine, many plants are used for treatment of kidney stones. In the present study, effect of Equaisetum arvense L. aerial parts hydro-alcoholic extract on calcium oxalate crystallization was studied in male rats. At first, hydro-alcoholic extract of plant at doses of 25, 50 and 100 mg/kg were prepared. Crystallization of calcium oxalate was induced by adding ammonium chloride and ethylene glycol in drinking water for 3 and 38 days, respectively. Control group was treated by drinking water. Experimental groups were treated by plant extract at doses 25, 50 and 100 mg/kg for 41 days, interperitoneally. After 41 days, animals were anesthetized by ether and left kidneys removed and put them in buffered formaldehyde. Specimens were prepared for histological studies and stained by H&E staining method. Results showed that treatment of extract decreased number of crystals in kidney sections of experimental animals in comparison with control group. Also, administration of plant extract decreased tubule-interstitial damages in treated animals. So, the plant could prevent formation of calcium oxalate crystals in kidney.