e0064 Micro RNAs are involved in the psychological stress-induced cardiac disorders in rats

Abstract

Aims: Psychological stress has become an important factor in the development of cardiac disorders. And psychological stess is also involved in percutaneous cardiovascular interventions (PCTs). MicroRNAs(miRNA) have been implicated in regulation of cardiovascular diseases, however, the exact miRNAs involved in different kinds of cardiovascular diseases are still unknown. Therefore, we investigated whether miRNAs are involved in the psychological stress-induced cardiac disorders. Methods and results: Psychological stress rat models were established by giving complex stimulation at different time during the daytime for two weeks. Adrenocorticotrophic hormone (ACTH) were used to estimate whether establishing the right models by using ELISA. During processing the psychological stress, body weight, blood pressure and electrocardiogram were measured every 3 days. Cardiac changes were detected by HE staining and electronic microscopy. MicroRNA micro array was used to analyse the different expression of miRNAs. After psychological stress, hypothalamic-pituitary-adrenal was activated in stress group compare to control group, which was evaluated by detecting ACTH. Rats performed behaviour changes first, then body weight increased slowly, while systolic blood pressure increased obviously in stress group from the 6th day to the 15th days. The ECG of all rats was normal before experiment, after stimulation lasted 2 weeks, the ECG record of different individuals in stress group showed different arrhythmia, atrial premature contraction, including sinus tachycardia, ventricular arrhythmia. Some of the ECG recorded from rat models also showed ST-T changes. The ultrastrcture and histology showed injury changes in stress group. Compared to the control group, there were different 55 miRNAs in stress models including upregulation of 20 and downregulation of left, among which miRNA-141, miRNA-382, miRNA-219-5p and miRNA-296 up-regulated, mrRNA-135a and miRNA-466b are significant down-regulated.Conclusions: Complex stimulation can induce psychological stress and cause cardiac injury, which may be a correct way to set up psychological animal model. MiRNAs change in stress rat models, including significant downregulation of miR-135a and miR-466b, while upregulation of miR-141, miR-382, miR-219-5p and miR-296, which maybe play important roles in psychological stress-induced cardiac disorders. (Supported by research grant NSFC 30940041).