[Effects of magnesium salts on the course of experimental calcium-oxalate urolithiasis]

Experimental urolithiasis was induced in 80 white non-inbred male rats by adding 0.75% ethylene glycol and 2% ammonium chloride to drinking water by Fan et al. After significant differences in crystalluria, oxaluria and urine pH were achieved in hyperoxaluric rats vs controls one, hyperoxaluric rats were given magnesium (Mg) salts Mg chloride, Mg L-aspartate either alone or in combination with pyridoxine hydrochloride (B6) in comparison with Mg sulfate and magne B6 (mg lactate in combination with B6) in a dose of 50 mg of elementary Mg per 1 kg of body weight. All the rats were fed with Mg-adequate diet containing 0.84 g of Mg oxide (0.5 g of elementary Mg per kg of diet). Calcium-oxalate urolithiasis has developed in rats taking ethylene glycol and ammonium chloride for 28 days. An urinary oxalates levels increased threefold, oxalate/creatinine--fourfold. Calcium oxalate crystals were detected in the urine of rats drinking solution of ethylene glycol and ammonium chloride, pH decreased by 20%, fractional excretion (FE) of Mg increased by 60%, FE of phosphate--by 58.2%, FE of calcium--by 95.8%, creatinine clearance lowered by 39.2% in comparison with intact group. Magnesium salts administration resulted in reduction of urine oxalates, crystalluria, phosphate excretion, Ca/Mg and oxalate/creatinine ratios, increased urine pH and creatinine clearance. Mg L-aspartate in combination with vitamin B6 appeared the most effective salt and significantly more effective than magnesium sulfate.