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Objective To investigate the effects of human umbilical cord mesenchymal stem cells (UC-MSCs ) on vascular endothelial growth factor ( VEGF ) and monocyte chemoattractant protein-1 ( MCP-1 ) of acute myocardial ischemia-reperfusion (AMI-R) injury in rats. Methods 24 Sprague-Dawley rats were randomly divided into sham group, AMI-R group and UCMSCs treatment groups on average. The rats were sacrificed on the 10th day after UCMSCs transplantation, and the myocardial tissues below the ligature were taken. The mRNA and protein expressions of MCP-1 of the tissue were detected by RT-PCR and Western Blot respectively, and the expression of VEGF protein was detected by immunohistochemistry. Results The relative expression levels of MCP-1 mRNA and the protein in UCMSCs group were significantly lower than those in sham group and AMI-R group (all P<0.05). The expression of VEGF protein in UCMSCs group was significantly higher than that in sham group and AMI-R group, the differences were statistically significant(all P<0.05). Conclusion UCMSCs transplantation can promote the angiogenesis and decrease the inflammation reaction in the treatment of acute myocardial ischemia-reperfusion injury.
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<p><b>OBJECTIVE</b>To explore the partial action mechanism and the myocardial protective effect differences between electroacupuncture (EA) preconditioning at "Neiguan"(PC 6) and "Taiyuan"(LU 9) in rats with acute myocardial ischemia-reperfusion injury.</p><p><b>METHODS</b>Ninety-six Wistar rats were randomly assigned into a sham-operation group, a model group, a Neiguan group and a Taiyuan group, 24 rats in each one. The rats in the Neiguan group and Taiyuan group were treated with EA (2 Hz in frequency, 1 mA in intensity) at "Neiguan" (PC 6) and "Taiyuan" (LU 9) respectively, 20 min per treatment, once a day for consecutive 7 days. The rats in the sham-operation group and model group were treated with immobilization for the same time, and no EA was given. The model of myocardial ischemia-reperfusion injury was established in the model group, Neiguan group and Taiyuan group 24 h after the end of EA, while the rats in the sham-operation group were treated with sham operation (no ligation was made during surgery). The myocardial ischemic size, infarction size, activity of protein kinase C (PKC) and expression of aquaporin1 (AQP1) in each group were detected.</p><p><b>RESULTS</b>Compared with sham-operation group, the myocardial ischemic size, infarction size, AQP1 expression and PKC activity in the model group were significantly increased (all<0.01); compared with the model group and Taiyuan group, the myocardial ischemic size, infarction size, PKC activity and AQP1 expression were significantly decreased in the Neiguan group (<0.01,<0.05). By Pearson correlation analysis, the changes of AQP1 expression were positively correlated with those of PKC activity after EA preconditioning.</p><p><b>CONCLUSIONS</b>EA preconditioning at "Neiguan" (PC 6) could significantly decrease myocardial AQP1 expression and PKC activity in rats with acute myocardial ischemia-reperfusion injuing, but the effect of EA preconditioning at "Taiyuan"(LU 9) is not obvious; its protective effect is likely to be achieved by inhibiting PKC activity and AQP1 expression.</p>
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Objective: To observe the effects of angiotensin II(Ang II) perfusion on transmural heterogeneity of Cx43 expression in the rabbit model with acute myocardial ischemia reperfusion (MIR), and investigate the role of rennin-angiotensin system in malignant ventricular arrhythmia induced by MIR. Methods: Twenty rabbits were randomly divided into MIR group (n = 10) and Ang II group (n = 10). MIR model was produced with traditional ligation and opening of the anterior descending coronary artery in all animal. The hearts in vitro in the MIR group and the Ang II group were perfused with simply improved Tyrode's solution and containing Ang II Tyrode's solution respectively. 90% monophasic action potential repolarization duration, transmural dispersion of repolarization, Cx43 protein (Cx43-pro) and mRNA (Cx43-Cq) expression in subepicardial, midmyocardial and subendocardial myocardium were measured in both groups. The greatest differences of Cx43-pro and Cx43-Cq among three myocardial layers were calculated and shown with ΔCx43-pro and ΔCx43-Cq respectively. Results: After Ang II perfusion, 90% monophasic action potential repolarization duration among three myocardial layer were significantly prolonged (P < 0.05 and P < 0.01), and transmural dispersion of repolarization also significantly increased compared with the MIR group (P < 0.05). Compare with the MIR group, three myocardial Cx43-pro and Cx43-Cq expression in the Ang II group were significantly decreased (P < 0.05 and P < 0.01), but ΔCx43-pro and ΔCx43-Cq were significant increased. Conclusions: Renin-angiotensin system increases transmural heterogeneity of Cx43 expression in the rabbit model with MIR by Ang II, and enlarge transmural dispersion of repolarization among three myocardial layers of left ventricular which induces malignant ventricular arrhythmia.
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OBJECTIVE@#To observe the effects of angiotensin Ⅱ(Ang Ⅱ) perfusion on transmural heterogeneity of Cx43 expression in the rabbit model with acute myocardial ischemia reperfusion (MIR), and investigate the role of rennin-angiotensin system in malignant ventricular arrhythmia induced by MIR.@*METHODS@#Twenty rabbits were randomly divided into MIR group (n = 10) and Ang Ⅱ group (n = 10). MIR model was produced with traditional ligation and opening of the anterior descending coronary artery in all animal. The hearts in vitro in the MIR group and the Ang Ⅱ group were perfused with simply improved Tyrode's solution and containing Ang Ⅱ Tyrode's solution respectively. 90% monophasic action potential repolarization duration, transmural dispersion of repolarization, Cx43 protein (Cx43-pro) and mRNA (Cx43-Cq) expression in subepicardial, midmyocardial and subendocardial myocardium were measured in both groups. The greatest differences of Cx43-pro and Cx43-Cq among three myocardial layers were calculated and shown with ΔCx43-pro and ΔCx43-Cq respectively.@*RESULTS@#After Ang Ⅱ perfusion, 90% monophasic action potential repolarization duration among three myocardial layer were significantly prolonged (P < 0.05 and P < 0.01), and transmural dispersion of repolarization also significantly increased compared with the MIR group (P < 0.05). Compare with the MIR group, three myocardial Cx43-pro and Cx43-Cq expression in the Ang Ⅱ group were significantly decreased (P < 0.05 and P < 0.01), but ΔCx43-pro and ΔCx43-Cq were significant increased.@*CONCLUSIONS@#Renin-angiotensin system increases transmural heterogeneity of Cx43 expression in the rabbit model with MIR by Ang Ⅱ, and enlarge transmural dispersion of repolarization among three myocardial layers of left ventricular which induces malignant ventricular arrhythmia.
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Objective Experimental study on effects of Yangxinshi tablets in the prevention and treatment of chronic is-chemic heart failure and acute myocardial ischemia reperfusion injury in order to provide a theoretical basis for its clinical appli-cation .Method Rat model of chronic ischemic heart failure and acute ischemia reperfusion mouse model of myocardial infarc-tion were constructed through coronary artery ligation .Those animals were randomized to sham operation group ,model group , positive drug group ,high Yangxinshi tablet dose group ,middle Yangxinshi tablet dose group ,low Yangxinshi tablet dose group .Rat electrocardiogram ,ultrasound ,ACE ,ACD ,TNF-a ,mouse myocardial infarction area ,CK ,LDH ,SOD and relat-ed factors were recorded during pre-dosing and post-dosing after modeling .Morphological changes were observed with cardiac pathological section .Results The biochemical indicators in model group were significantly different from sham operation group with statistical significance (P<0 .001) .Compared to the model group ,positive drug group and high Yangxinshi tablet dose group exhibited biochemical differences with statistical significance (P<0 .001 ,P<0 .01 ,P<0 .05) ,significant myocardial in-farction area reduction (P<0 .01 ,P<0 .05) ,improvement in myocardial cells and reduction in the cell infiltration .Conclusion Yangxinshi tablets have preventive and therapeutic effects on chronic ischemic heart failure and acute ischemia reperfusion in-jury .