柔红霉素对大鼠心肌细胞脑利钠肽表达影响的研究

目的研究柔红霉素对大鼠心肌细胞脑利钠肽表达的影响。方法体外分离培养心肌细胞,实验分正常对照组、柔红霉素组（柔红霉素0．2mg／L加入培养液）及柔红霉素＋1、6-二磷酸果糖组（柔红霉素0．2mg／L及1、6-二磷酸果糖2mg／ml分别加入培养液）,用四唑盐比色试验、RT—PCR及Western印迹等方法检测各组细胞增殖及脑利钠肽表达。结果应用柔红霉素后大鼠心肌细胞脑利钠肽mRNA表达与内参GAPDH表达平均灰度比值从（0．94±0．25）减少到（0．32±0．18,P〈0．01）,蛋白印迹与内参GAPDH平均光度比值从（0．82±0．13）减少到（0．40±0．09,P〈0．01）,加入1、6-二磷酸果糖干预后其mRNA表达与内参GAPDH平均灰度比值及蛋白印迹与内参GAPDH平均光度比值分别为（0．36±0．22）和（0．42±0．11）,均无明显增加。结论柔红霉素对心肌细胞脑利钠肽表达呈抑制作用,1、6-二磷酸果糖不能逆转其抑制作用。

Effects of daunorubicin on the expression of brain natriuretic peptide gene in myocardial cells: an in vitro experiment with cultured myocardial cells from rats

OBJECTIVE: To investigate the effects of daunorubicin (DNR) on the gene expression of brain natriuretic peptide (BNP) in myocardial cells. METHODS: Myocardial cells were isolated from neonatal Wistar rats, cultured, and added with DNR of the concentrations of 0, 0.02, 0.2, and 2 mg/L respectively so as to calculate the maximum non-toxic concentration of DNR. The cultured rat myocardial cells were divided into 3 groups, DNR group, added with DNR 0.2 mg/L, DNR+fructose-1, 6-diphosphate (FDP) group, added with DNR 0.2 mg/L and FDP 2 mg/ml, and control group. The viability of the myocardial cells was examined by MTT method. RT-PCR and Western blotting were used to detect the mRNA expression and protein expression of the BNP gene. RESULTS: Toxicity test showed that the maximum non-toxic concentration of DNR was 0.2 mg/L. Western blotting showed that the average grey level ratio of BNP/GAPDH of the DNR group was 0.40+/-0.09, not significantly different from that of the DNR+FDP group (0.42+/-0.11, but significantly lower than that of the control group (0.82+/-0.13, P<0.01). CONCLUSION: DNR suppresses the expression of BNP gene in myocardial cells and FDP cannot reverse the suppressing effect.