The effects of counterions of citric acid and EDTA on the crystallization of calcium oxalate(CaO x )were in-vestigated in silica gel with a doubl e diffusion technique.The ability o f inhibiting the growth and aggregation of CaO x crystal and the ability of inducing f ormation of COD follows:potassium c itratesodium citrate >citric acid.Na 2 EDTA had a stronger ability to inhibi t the aggregation of CaO x crystals than that of EDTA,but a weak er ability to inhibit nucleation and growth of C aO x crystals.Since COM exhibits a greater degree of attachment to renal tubule cells in culture compared with COD,t hat is,COD is easy to be expelled from the body along with the urine.So both inducing formation of COD and in hibiting growth and aggregation of CaO x crystal can decrease the probability of urinary stones.These results hav e positive significance in the prevention and cure of urinary stones clin ically.
The influence of mucin on the growth of calcium oxalate crystals was investigated by means of scanning electron microscopy and X-ray diffraction. In the control systems without mucin, calcium oxalate monhydrate(COM) crystals were the polymorphs without uniforn shape, and the (010) crystal face of COM was preferential grown.However,in the presence of mucin both the size and number of COM crystals were decreased, and the intensity of the diffraction peak of (101) face was strengthened in the debt of (010) face of COM crystals. It indicated that mucin can inhibit both the nucleation and growth of COM crystals, so mucin can prevent the formation of CaOxa stones.
The animal models of calcium oxalate stones induced by hyperoxaluria, hypercalciuria and lack of vitamin were summaried, and effects of different inhibitors and Chinese traditional medicines on the formation of calculi in animals were discussed.