title: Chemical urolithiasis 2. Thermodynamic aspects of bladder stone induction by terephthalic acid and dimethyl terephthalate in weanling Fischer-344 rats.
abstract: The induction of calcium terephthalate (CaTPA) calculi in the urinary tract of rats ingesting terephthalic acid (TPA) or dimethyl terephthalate is a result of supersaturation with respect to the stone components. The solubility product of CaTPA was determined in water at 37 degrees C, and its value in urine of exposed weanling Fischer-344 rats was calculated based on the electrolyte concentrations of freshly-collected, microliter urine samples. The value of the solubility product in urine is equal to the minimum concentration product of free Ca2+ and TPA2- at which crystallization can occur; hence, the urinary solubility product is a parameter that is useful for risk assessment. Estimates of the TPA concentrations required to induce crystals or stones in normal human urine are presented.
mesh_terms: D000818:Animals; D002769:Cholelithiasis / Q000139:chemically induced* / Q000378:metabolism; D004573:Electrolytes / Q000652:urine; D005260:Female; D006801:Humans; D008297:Male; D010795:Phthalic Acids / Q000378:metabolism / Q000633:toxicity*; D051381:Rats; D011916:Rats, Inbred F344; D012306:Risk; D012995:Solubility; D013816:Thermodynamics
chemical_list: D004573:Electrolytes; D010795:Phthalic Acids; C011363:terephthalic acid; C004782:dimethyl 4-phthalate