effect of hardwater on the prevention and treatment of calcium oxalate nephrolithiasis in rats

Background: there is a folk belief that drinking ramsar spring mineral water (rsw) is a remedy for renal stones. objectives: this study aimed to evaluate the effect of rsw on prevention or treatment of nephrolithiasis in male wistar rats and identify the constituents of the water. methods: nephrolithiasis was induced by providing drinking water containing 1% ethylene glycol (eg) for two weeks in male wistar rats. the animals were divided into prevention and treatment groups, each contained five sub-groups (10 rats for each). prevention groups were treated for two weeks: control group (without treatment), eg group (1% ethylene glycol in drinking water), rsw 5, 10, and 15% groups (1% ethylene glycol + rsw 5, 10, and 15% in drinking water). the treatment groups received 1% eg for two weeks, then it was discontinued, and the rsw (10, 15, and 20%) was added to the drinking water for the next two weeks. the calcium oxalate (caox) depositions in the kidneys' tubules were evaluated by hematoxylin and eosin staining. the spring water was analyzed for its constituents. results: calcium oxalate crystals were significantly increased in eg group (in the prevention protocol) as compared to the control group (p < 0.01). moreover, rsw did not significantly prevent caox crystals but alleviated caox crystals at 15 and 20% concentrations in the treatment protocol (p < 0.001). conclusions: the hard water of ramsar spring reduced caox crystals in nephrolithiatic rats, which may be due to its high calcium and magnesium content.