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BACKGROUND: Electrical stimulation at different intensity, frequency and time on the human body may produce a variety of pathophysiological reactions. OBJECTIVE: To observe the effects of surface electric-impulse stimulation on heart rhythm and heart rate in mice. METHODS: Thirty Kunming mice were randomly divided into three groups, each group contained 10 mice. Electrical stimulation at different voltage, time and frequency was respectively applied to the three groups. The stimulus power was supplied by BL-420F Data Acquisition & Analysis System. The II lead electrocardiogram was recorded. The systemic reactions and local body changes of mice were observed.
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BACKGROUND:The treatment of autologous pericardium transplantation has been widely applied in clinics, mainly involving cardiovascular repair and reconstruction, the treatment of ocular surface disease. The study addressing protection effects of autologous pericardium transplantation on the heart with ischemia injury is rarely reported. The investigations on the safety and protection effects of autologous pericardial transplantation on the heart with ischemia injury are of important significance. OBJECTIVE:To explore effect of autologous pericardial transplantation on cardiac electrical activity and the protective effects on myocardial ischemia. METHODS:Rongchang pork pigs and Sprague-Dawley rats were randomly divided into three groups:autologous pericardium transplantation, myocardial ischemia, and myocardial ischemia+autologous pericardium transplantation. The model of myocardial ischemia was established by ligation of the left anterior descending coronary artery in the groups of myocardial ischemia and myocardial ischemia+autologous pericardium transplantation. The model of transplantation was established by autologous pericardium transplant with flap in the groups of autologous pericardium transplantation and myocardial ischemia+autologous pericardium transplantation. RESULTS AND CONCLUSION:Porcine electrocardiogram monitoring results showed that, superventricular premature beat was frequently observed in each group of pigs;the ventricular premature beat was occasional observed in autologous pericardium transplantation group, ventricular tachycardia and ventricular fibril ation did not appear. Compared with myocardial ischemia group, the ventricular premature beat decreased and the heart function was improved in myocardial ischemia+autologous pericardium transplantation group (P<0.05). Rat electrocardiogram monitoring results showed that, the ventricular fibril ation did not appear in autologous pericardium transplantation group, the lethal ventricular fibril ation did not appear in myocardial ischemia and myocardial ischemia+autologous pericardium transplantation groups. Compared with myocardial ischemia group, the heart function was improved, the apoptosis index decreased, the expressions of Bcl-2 protein increased, the expressions of Caspase-3 protein decreased in myocardial ischemia+autologous pericardium transplantation group (P<0.05). The autologous pericardium transplantation with flap cannot induce malignant ventricular arrhythmia and is relatively safe;the ventricular premature beat is reduced, the cardiac function is improved, which is possibly related to the inhibition of apoptosis in myocardial ischemic area.
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ObjectiveTo investigate the effects of propofol and etomidate on apoptosis in hippocampal neurons in rats.MethodsOne hundred and forty male 4 weeks old SD rats were randomly divided into 7 groups (n =20 each):control group (group C) ; groups P1,2,3 received intraperitoneal (IP) propofol 50,100 and 200mg/kg and groups E1,2,3 received IP etomidate 10,30 and 60 mg/kg respectively.Arterial blood samples were obtained at 2 h after the animals were fully awake for blood gas analysis.The animals were then sacrificed and their brains removed for microscopic examination of the ultrastructure of neurons in hippocampal CA1 area and detection of Survivin and Caspase-3 mRNA and protein expression in hippocampus by RT-PCR and Western blot analysis.ResultsThere was no significant difference in PaO2,PaCO2,SaO2,HCO3-,BE and pH value among the 7 groups.The neurons in CA1 area were basically normal in groups C,P1 and E1 while condensation of the chromatin of the nucleus and apoptotic bodies were observed in groups P3 and E3.Caspase-3 mRNA and protein expression was significantly up-regulated while Survivin mRNA and protein down-regulated in groups P3 and E3.Conclusion High dose of propofol and etomidate may induce apoptosis in hippocampal neurons in rats by up-regulation of Caspase-3 expression and down-regulation of Survivin expression.
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Objective To investigate the effect of morphine on the expression of p53 mRNA and E2F-1 mRNA in human gastric carcinoma cell line MGC-803 .Methods The human gastric cancer cell line MGC-803 was purchased from Cell Biology Research Institute, Chinese Academy of Sciences, and cultured in DMEM liquid culture mediun. The cells were seeded in 6-well plates (1 × 103/ml or 2 × 105/ml, 1 ml/well) and divided into 2 groups (n = 18 wells each):group Ⅰ normal control (group C); group Ⅱ was exposed to 10 μmol/L morphine (group M). The proliferation of the cells was determined by colony formation assay at 7 day of incubation with morphine. The expression of p53 mRNA and E2F-1 mRNA was detected and the ulrastructure of the cells examined with transmission electron microscope after being incubated with morphine for 24 h. Results The proliferation of the cells and E2F-1 mRNA expression were significantly lower and p53 mRNA expression was significantly higher in group M than in group C (P ＜ 0.05). The nuclear evelope was intact and the nucleolus and chromosomes were clearly visible in group C, while in group M fragmentation of nuclear envelope and nucleolus and apoptotic bodies were observed. Conclusion Morphine can inhibit the proliferation of the cells and accelerate the cell apoptosis through up-regulating the expression of p53 gene and down-regulating the expression of E2F-1gene in human gastric carcinoma cell line MGC-803.