To explore the role of mechanosensitive potassium channel TREK-1, Western blot analysis was used to investigate the expression changes of TREK-1 in left ventricle in acute mechanically stretched heart. Forty Wistar rats were randomly divided into 8 groups (n=5 in each group), subject to single Langendorff perfusion for 0, 30, 60, 120 min and acute mechanical stretch for 0, 30, 60, 120 min respectively. With Langendorff apparatus, an acute mechanically stretched heart model was established. There was no significant difference in the expression of TREK-1 among single Langendorff perfusion groups (P>0.05). As compared to non-stretched Langendorff-perfused heart, only the expression of TREK-1 in acute mechanically stretched heart (120 min) was greatly increased (P<0.05). This result suggested that some course of mechanical stretch could up-regulate the expression of TREK-1 in left ventricle. TREK-1 might play an important role in mechanoelectric feedback, so it could reduce the occurrence of arrhythmia that was induced by extra mechanical stretch.
Feedback ; Heart Ventricles/*metabolism ; Mechanotransduction, Cellular ; Potassium Channels, Tandem Pore Domain/*metabolism ; Random Allocation ; Rats, Wistar ; Stress, Mechanical

To explore the role of mechanosensitive potassium channel TREK-1, Western blot analysis was used to investigate the expression changes of TREK-1 in left ventricle in acute mechanically stretched heart. Forty Wistar rats were randomly divided into 8 groups (n=5 in each group),subject to single Langendorff perfusion for 0, 30, 60, 120 min and acute mechanical stretch for 0, 30,60, 120 min respectively. With Langendorff apparatus, an acute mechanically stretched heart model was established. There was no significant difference in the expression of TREK-1 among single Langendorff perfusion groups (P＞0.05). As compared to non-stretched Langendorff-perfused heart, only the expression of TREK-1 in acute mechanically stretched heart (120 min) was greatly increased (P＜0.05). This result suggested that some course of mechanical stretch could up-regulate the expression of TREK-1 in left ventricle. TREK-1 might play an important role in mechanoelectric feedback,so it could reduce the occurrence of arrhythmia that was induced by extra mechanical stretch.

The expression of stretch-activated potassium channel TREK-1 mRNA and protein of hypertrophic myocardium was measured. Using a model of hypertrophy induced by coarctation of abdominal aorta in male Wistar rats, the expression of TREK-1 mRNA and protein was detected by using semi quantitative RT PCR and Western blot respectively. At 4th and 8th week after constriction of the abdominal aorta, rats developed significant left ventricular hypertrophy. As compared to sham operated group, stretch activated potassium channel TREK-1 mRNA was strongly expressed and protein was up regulated in operation groups (P＜0.05). It was concluded that the expression of TREK 1 was up regulated in hypertrophic myocardium induced by chronic pressure overload in Wistar rats.

Objective To explore the predictive value of serum soluble osteoclast-associated receptor(sOSCAR)for cardiovascular adverse events after percutaneous coronary intervention(PCI)in patients with acute non-ST segment elevation acute myocardial infarction(NSTEMI).Methods From January 2020 to Jan-uary 2022,124 NSTEMI patients admitted to Weifang People's Hospital who underwent PCI were selected as the NSTEMI group,and another 100 healthy volunteers in the same period were selected as the control group.The NSTEMI patients were classified into 31 cases of poor prognosis and 93 cases of good prognosis group ac-cording to whether major adverse cardiovascular events occurred 1 year after PCI.Multivariate Logistic regres-sion model was constructed to analyze the factors affecting the prognosis of NSTEMI patients after PCI,and receiver operating characteristic(ROC)curve was drawn to analyze the predictive value of sOSCAR level on the prognosis of NSTEMI patients after PCI.Results Compared with the control group,serum angiopoietin-2(Ang-2)levels were increased and sOSCAR levels were decreased in the NSTEMI group(P＜0.05).At 1-year follow-up,the incidence of poor prognosis after PCI in 124 NSTEMI patients was 25.00％(31/124).Multivariate Logistic regression analysis showed that increasing age and Ang-2 were independent risk factors affecting the prognosis after PCI in patients with NSTEMI(P＜0.05),and elevated left ventricular ejection fraction and elevated sOSCAR were independent protective factors(P＜0.05).ROC curve analysis showed that the area under the curve of serum Ang-2 and sOSCAR levels combined to predict the prognosis after PCI in NSTEMI patients was 0.865,which was greater than that of serum Ang-2 and sOSCAR levels alone,which were 0.791 and 0.786(P＜0.05).Conclusion Serum sOSCAR level is decreased in patients with NSTEMI and is closely related to the poor prognosis of patients after PCI.Serum sOSCAR combined with Ang-2 has a high predictive value for the poor prognosis of NSTEMI patients after PCI.

Extracorporeal membrane oxygenation(ECMO) is a type of technique which can be used to replace patients' pulmonary function and cardiac function effectively. Since 2000s,the technique began to apply in pediatric patients but still developed very slowly. As well,patients transport with ECMO is another problem for the pediatricians. So,it is necessary to raise the conception of pediatric ECMO transport network and construction of the network. In this paper,the concept of pediatric ECMO transport network,current status of transport,the characteristics and constitution of pediatric ECMO transport network,indication for transport of pediatric ECMO,the problems in the construction of network were introduced to promote the construction of the network.