A comparative study of kidney lithogenic agents in Wistar rats by invasive and noninvasive methods

Urolithiasis has been globally reported in humans and animals due to multiple factors. Research on the management and treatment of urolithiasis would benefit if suitable lithogenic agents replicate various degrees of severity as seen in humans. Based on the literature, ethylene glycol with ammonium chloride and sodium oxalate are the commonly used agents for the induction of kidney stones in rats, but the duration of the induction period varies between the researchers. Hence, in the present study, ethylene glycol with 1 % ammonium chloride (EG1AC), ethylene glycol with 2 % ammonium chloride (EG2AC) in drinking water for 14 days, and sodium oxalate (SO) at 70 mg/kg body weight administered through intraperitoneal route for 14 days and post monitored up to 50 days to know the kidney damage. In the studies on urolithiasis model, the severity of kidney damage is determined based on renal tissue analysis, urine, and serum parameters. For the first time, instantaneous noninvasive ultrasound scorecard technique has been used to assess the severity of kidney damage in urolithiasis. Based on the urine, serum, renal tissue, and ultrasound examinations, one day is enough for sodium oxalate for kidney stone formation, whereas seven days for EG1AC or EG2AC and the degree of kidney severity were in the order of sodium oxalate > EG2AC > EG1AC from days 1 to 50. Ultrasound scorecard can be effectively used to evaluate kidney stone formation and damage without sacrifice of animal from day 1 onwards.