Expression of S100B during heart failure in rats / 中华急诊医学杂志

ABSTRACT

Objective To evaluate the value of S100B gene on cardiovascular remodeling in rats with abdominal aorta coarctation.Method Sprague-Dawley rats(sanitary degree,male),weighring(220～240)g,were used in the study.They were provided by College of Medicine,Zhejiang University.The abdominal aortas of rats were isolated and constricted so as to establish models of heart failure;the abdominal aortas of another ten rats were isolated but not ligated(sham-operation group).After one week,the 20 rats were alive and randomly divided into 2 groupsoperation group(n=10)and Carvidilol-operation group(Car group,n=10).Car Group was treatedwith 2 mg·kg-1per day Carvedilol and operation group was administered with the same doses of normal saline.After 4 weeks,a catheter was inserted through the right jngular artery into the left ventricle to record hemodynamic.Then all rats were euthanized,and the heart tissues were rapidly excised,rinsed with PBS.The left ventricles were then cut into two parts at the equatorthe upper sections were fixation,the lower sections were stoted at-80℃,at 100 mg per tube.LV transverse section(4μm thick)was subjected to S100B immunehistoc- hemistry.RNA was iselated from tissues by Trlzol to determine levels of S100BmRNA and β-actinmRNA by RT- PCR.The data was expressed as(x±s);One-way analysis of variance was used for comparison among groups, and Student-Newman-Keulsa test for comparison between two groups.Statistical significance was set at P＜0.05. Results In Operation Group,there was a decrease in maximal rate of systolic and diastolic of left ventricular pressure(±dp/dtmax)[(1543.6±277.9)mmHg/s vs.(2640.4±481.3)mmHg/s and(-1352.5±202.3) mmHg/s vs.(-1873.2±412.3)mmHg/s];and an increase in left ventricular end diastolic pressure(LVEDP) [(24.8±5.2)mmHg vs.(2.1±0.7)mmHg]compared with sham-operation group(P＜0.01,P＜0.01 and P＜0.05).And in Car group,the level of LVEDP was just in the midst of the Operation Group and sham-opera- tion group,and had statistical significance(P＜0.01);while±dp/dtmac[(2372.3±92.6)mmHg/s and (-1786.4±62.6)mmHg/s]were much higher than those in operation group(P＜0.01).There were no any S100B positive cells and expression of S100B mRNA in sham-operation group;while there were much more S100B positive cells in operation group than those in Car group(P＜0.01).The expression of S100B mRNA in operation group was more pronounced than that in Car group.Changes in expression of S100BmRNA were positively correlat- ed with changes in LVEDP(r=0.847,P＜0.01);while changes in expression of S100BmRNA were negatively correlated with changes in±dp/dt max(r=-0.853 and-0.689,beth P＜0.01).Conclusions There was hish expression of S100B in myocytes from rats with experimental heart failure and negative correlation between the expression of S100B and heart function.It indicated that S100B could play a negative role in heart failure.