在体外模拟胆结石形成的实验中,选取腺苷-5’-三磷酸(ATP)-金属离子-脱氧胆酸(DC)凝胶体系进行了分形/周期有序结构的生长实验,研究ATP对Co^2+-脱氧胆酸凝胶体系形成的分形/周期沉淀的影响,用FTIR表征有序沉淀物的结构。结果表明:在ATP存在下的Co^2+-DC凝胶体系中,可形成周期沉淀及分形结构共存的复杂时空图案,ATP对Co^2+-脱氧胆酸凝胶体系形成的图案模式较AMP的影响显著,体系的图案从分形模式转化为周期沉淀,ATP、脱氧胆酸钠、Co^2+存在复杂的相互作用,生成透明晶体新物质;红外光谱结果显示该晶体为脱氧胆酸,周期沉淀物为ATP、DC共同与金属离子配位的结果。此结果说明核苷酸作为重要的生命物质在结石形成过程中起到重要作用,结石的形成具有复杂的、非线性化学特性。
In the simulation experiments in vitro of the formation of gallstone,adenosine-triphosphate(ATP)-Co^2+-deoxycholic acid(DC) gel system was chosen to study the periodic precipitation progress. The effect of ATP on the Co^2+-DC gel system was also determined,and the structure of the periodic precipitation formed was characterized by FTIR. The results show that the patterns formed in the systems with ATP are different,ATP affected the rate and structure of precipitation through its variable participation in the metal coordination complexes as judged by the phosphate P-O bands and the deoxycholate COO^-symmetric and asymmetric vibration bands as measured by FTIR. Theses spectroscopic differences were correlated with color and pattern differences in the precipitates. ATP has a more remarkable function than AMP to the modes of patterns,meanwhile the system patterns transform from fractal to periodic precipitation. There is a complex interaction among ATP,sodium deoxycholic and Co^2+ with a transparent crystal produced. The crystal is deoxycholic acid and the periodic precipitation is composed of ATP and DC covalent to Co^2+. These results indicate that stone formation and remodeling is a dynamic,nonlinear progress. Much of the precipitate,as judged by local differences in composition,is not in equilibrium with the general gel environment. The authors conclude that the formation of gallstone features complex and nonlinear chemical character,in which nucleotides as living material play a very important role.