大鼠放射性心脏损伤模型建立及其早期检测指标

Establishment of radiation-induced heart damage rat model and its early detection indicators

目的探索SD大鼠心脏15Gy分3次照射所致放射性心脏损伤模型的建立及其早期检测指标变化,并分析联合重组人血管内皮抑制素(Endostar)的影响。方法75只SD成年雄性大鼠随机分为空白对照组(C组)、Endostar组(E组)、25Gy照射组(MHD25组)、15Gy照射组(MHD15组)、15Gy照射联合Endostar组(MHD15+E组),分别在干预后24、48h和15d取血测CK、CK-MB、LDH和CRP,在1、3、6个月行大鼠心脏超声心动图后每组随机处死5只大鼠取心肌组织行HE、Masson染色。双因素方差分析统计。结果与C组比较,6个月MHD15组出现心肌纤维化晚于MHD25组出现。各照射组在3个月后出现射血分数、缩短分数降低(P<0.05),且程度相似(P>0.05)。心肌酶及炎症因子各组间相近(P>0.05)。结论大鼠心脏15Gy分3次照射早期可造成心脏功能损伤,如射血分数、缩短时间降低,晚期可导致心肌纤维化,并比高剂量照射延迟出现。照射基础上联合Endostar对大鼠的放射性心肌损伤无明显影响。

Objective To explore the establishment of radiation-induced heart damage(RIDH)SD rat models caused by irradiation of 15Gy/3f and the changes in early detection indicators,and evaluate the effect of irradiation combined with recombinant human endostatin(Endostar).Methods 75 adult male SD rats were randomly divided into the blank control group(C group),Endostar group(E group),25Gy irradiation group(MHD25 group),15Gy irradiation group(MHD15 group)and 15Gy irradiation combined with Endostar group(MHD15+E group),respectively.Blood sample was taken to measure the CK,CK-MB,LDH and CRP at 24h,48h and 15d after corresponding interventions.After cardiac echocardiography at 1,3 and 6 months,5 rats in each group were randomly sacrificed and myocardial tissues were collected for HE and Masson staining.Two-way ANOVA was employed for statistical analysis.Results Compared with group C,myocardial fibrosis were observed in the MHD15 group at 6 months(P<0.05),which occurred later than that in the MHD25 group.Ejection fraction(EF)and fractional shortening(FS)were significantly decreased after 3 months in each irradiation group(all P<0.05),whereas the degree of decrease was similar among all groups(all P>0.05).The expression levels of myocardial enzymes and inflammatory cytokines did not significantly differ among different groups(all P>0.05).Conclusions In the early stage,exposure to 15Gy/3f irradiation can cause cardiac function damage in SD rat hearts,such as the reduction of EF and FS,and even lead to myocardial fibrosis in the late stage,which is delayed and less severe than high-dose irradiation.Irradiation combined with Endostar has no significant effect on radiation myocardial injury in rats.