ABSTRACT
Objective To investigate the dynamic changes of osteopontin (OPN) in the guinea pig model of cholesterol gallstone disease.Methods Forty-four guinea pigs were randomly assigned to cholesterol gallstone group and control group.The animals were sequentially killed on Day 7,14,28,42,56 and 70 after operation.The expressions of OPN mRNA in gallbladder and liver tissues were detected by real-time PCR.The changes of OPN,mucin,α1-acid glycoprotein (AAP) and apolipoprotein A1 (APOA1) in bile and blood plasma were detected by ELISA kits.Results The expression of OPN mRNA in gallbladder and liver tissues increased gradually and reached the peak in the 6th week,and then decreased.The increased expression of OPN in bile in the gallstone group started from the 1st week and reached the peak in the 6th week (P ＜ 0.05),which gradually decreased to the baseline in the 10th week (P ＞ 0.05).The expressions of OPN in bile and blood demonstrated similar trends,while the peak time in blood samples was much earlier (4th week).The changes of APOA1 in bile and blood were similar to OPN,although there was no advanced peak value in blood.The levels of mucin and AAP in bile and blood increased after operation,and were kept at high level throughout the study.Conclusions OPN is involved in the whole process of cholesterol gallstone formation,which may be associated with other nucleation-active factors.