Establishment of radiation-induced heart damage rat model and its early detection indicators / 中华放射肿瘤学杂志

ABSTRACT

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 (MHD 25 group), 15Gy irradiation group (MHD 15 group) and 15Gy irradiation combined with Endostar group (MHD 15+ 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 MHD 15 group at 6 months ( P<0.05), which occurred later than that in the MHD 25 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.