IN VITRO EFFECT OF ACETYLSALICYLIC ACID ON CALCIUM OXALATE CRYSTALLIZATION: AN APPROACH TO ANTILITHIASIS

摘要

Objective : In recent years, significant progress has been made in identifying and counting physico-chemical processes involved in urinary stone formation. The ability of urine to inhibit calcium oxalate crystallization is considered an important mechanism against stone formation. Several natural substances were tested to inhibit calcium oxalate crystallization. In the present study, we evaluate the effects of acetylsalicylic acid, also known as Aspirin, as an inhibitor of calcium oxalate crystallization in vitro. Methods: The nucleation and aggregation of calcium oxalate crystals were studied using turbidimetric 400-sec time course measurements of optic density at 620 nm after mixing solutions containing calcium chloride and sodium oxalate at room temperature, pH 5.7. The formation of crystals is induced by the addition of the oxalate to calcium solution. The effects on calcium oxalate crystal growth of acetylsalicylic acid with various concentrations were examined. The maximum increase of optic density in the course of time reflects maximum rate of formation of new particles. After reaching equilibrium, a progressive decrease of optic density with time is observed. Rate of aggregation is derived from the maximum decrease in optic density. Results: The results showed that if a concentration of acetylsalicylic acid is more than 1,66 mM both rate of formations of new particles and Rate of aggregation decreased (P<0.05). Conclusion: acetylsalicylic acid has a significant effect on nucleation as well as on crystal growth stage; consequently, it inhibits the crystal formation of calcium oxalate urinary lithiasis. Keywords : Urolithiasis, Calcium oxalate, Crystallization, Acetylsalicylic acid, Inhibition.