Constructing and assessing a rat model of sepsis-induced myocardial dysfunction / 中国组织工程研究

ABSTRACT

BACKGROUND: It is currently believed that myocardial mitochondrial structure and function damage play a key role in sepsis-induced myocardial dysfunction. OBJECTIVE: To construct a rat model of sepsis-induced myocardial dysfunction and provide an effective experimental method for studying the disease. METHODS: Seventy-two SPF male Sprague-Dawley rats were randomly divided into control group (n-28) and lipopolysaccharide (LPS) group (n=44). Twenty rats were randomly selected from each group for observation of 10 days of survival. According to the post-modeling phase, the remaining 24 rats of the LPS group were divided into three subgroups, LPS 6-hour group, LPS 12-hour group and LPS 24-hour group, with 8 rats in each group. A sepsis model was constructed by intraperitoneal injection of 10 mg/kg LPS in the LPS group, and the control group was injected with an equal volume of normal saline. Echocardiographic examination of cardiac function was performed at each phase in each LPS subgroup. Myocardial histopathological morphology was observed by light microscopy, and myocardial ultrastructure was observed by transmission electron microscopy. Serum cardiac troponin and brain natriuretic peptide levels were measured by ELISA. The study was approved by the Ethic Committee of General Hospital of Ningxia Medical University in China (approval No. 2018-320). RESULTS AND CONCLUSION: Compared with the control group, the 10-day survival rate of rats in the LPS subgroups was lower. Compared with the control group, there was no reduction in left ventricular ejection fraction and left fractional shortening in the LPS 6-hour group (both P > 0.05). While in the LPS 12-hour group and LPS 24-hour group, the left ventricular ejection fraction and left fractional shortening significantly decreased (all P < 0.01), and the decrease was more obvious with time (all P < 0.01). Compared with the control group, the serum cardiac troponin and brain natriuretic peptide levels were significantly increased in the LPS 12-hour group and LPS 24-hour group (all P < 0.01), and the serum cardiac troponin and brain natriuretic peptide levels gradually increased with LPS injection time (all P < 0.01). The myocardial pathological morphology and ultrastructure of the LPS subgroups showed obvious damage compared with the control group, and the damage was more obvious with the prolongation of LPS injection time. In this experiment, we successfully constructed a stable and reliable model of sepsis-induced myocardial dysfunction in rats, which is an ideal animal model for clinical research of sepsis cardiomyopathy.