Myocardial Neovascularization Of Rats With AMI By Endothelial Progenitor Cells Mobilization

Objective:To observe the consequence of Endothelial Progenitor Cells (EPCs) mobilization and myocardial neovascularization by treatment with Fluvastatin、 erythropoietin(EPO) and Qi Shen Yi Qi extractum in Wistar rats with acute myocardial infarction (AMI), and to observe the diversity of myocardial infarction size and the diversity of survival rate between control group and experimental group, we try to provid some evidence to explore a new method of treatment to AMI.Methods:①Adult Wistar rats with AMI was established by left anterior descending branch deligation after opening the thorax.②the rats was randomly divided into7groups:the group A (normal group,n=8), the group B (n=10, only feed on Qi Shen Yi Qi extractum100mg·kg-1·d-1×28without operation), the group C (n=10, the sham operation group, only open the thorax without coronary artery deligation), the group D (n=19,only with AMI), the group E (n=14, treated with Qi Shen Yi Qi extractum100mg·kg-1·d-1×28after AMI), the group F (n=13, treated with Fluvastatin4mg·kg-1·d-1×28after AMI), the group G (n=14, treated with EPO1000U kg-1subcutaneously at operation day, the following day and7th day after AMI).③Mononuclearcells(MNCs) in peripheral vein blood was abstracted by density gradients centrifugalization, EPCs was staining together with a monoclonal antibody against rat with fluorescein isothiocyanate (FITC)-indirect conjugated CD133, and Phycoerythrin (PE)-conjugated CD34monoclonal anti-rat antibody was used as secondary antibody. EPCs was examined by Flow Cytometry Analysis.④The infarct size was calculated by the method of measureing midline infarct arc length, with Image-pro6.0image manipulation system, after collecting image under light microscope in masson stain slices. Immunohistochemical stain of anti-rat CD31monoclonal antibody was used to detect the density of myocardial neovascularization in myocardial infarction region, perim infarction region and no myocardial infarction region.⑤the comparison of survival rate between control group and experimental groups was carry out by chi square test.Results:(1)Animal AMI model:The number of survial rats in experimental groups(including group C, group D, group E, group F and group G) after operation is 10,17,11,11,9. The last number of survival rats after28days is9,8,9,8,7. The survival rate in every experimental group is90.00%,47.06%,81.82%,72.73%,77.78%. After chi square test, there were no significant statistical difference among group E, group F and group G (x=0.261,p>0.05). The comparison of survival rate between group D and the total survival rate of the three treatment groups were statistical diference(χ2=4.55, P<0.05).(2)EPCs mobilization:①In7th days, the number of EPCs in group D had increased to31.89±4.99/2×105MNCs, and there were statistical difference compaired with group A (P<0.05); there were no significant statistical difference between group A (19.88±4.91/2×105MNCs) and group C(22.33±5.43/2×105MNCs)(P>0.05); there were significant diference between group B(42.00±6.09/2×105MNCs)and groupA(P<0.05); there were significant diference between group E(44.56±7.54/2×105MNCs)and group D(P<0.05); there were no significant statistical difference among group F (29.63±6.59/2×105MNCs), group G(35.14±3.72/2×105MNCs) and group D(P>0.05), but there was a increased trend between group G and group D.②In14th days, the number of EPCs in group E had increased to54.44±6.04/2×105MNCs, and there were statistical difference compaired with group D (33.50±7.87/2×105MNCs), groupF(26.13±10.55/2×105MNCs) and group G(45.43±8.22/2×105MNCs)(P<0.05), there were statistical difference compaired with groupD in7th days(P<0.05); there were statistical difference between group D and group G; there were yet no statistical difference between group D and group F. Between the number of EPCs in7th days and the number of EPCs in14th days, there were too significant statistical diference in group A, group C, group D and group F(P>0.05). but there were significant increasing in group B, group E, group G (P<0.05).(3)The comparison of capillary densitiy:①The capillary densitiy in myocardial infarction region were higher in group E(19.86±3.14/mm2), group F (10.75±1.61/mm2), group G (14.86±2.87/mm2) than in group D (5.09±2.33/mm2)(P<0.05), and the capillary densitiy in group G was higher also than group F(P<0.05).②In perim infarction region, significant difference were also found between group F(17.53±2.35/mm2) and group D(8.55±2.40/mm2)(P<0.05), The capillary densitiy in group E (22.38±3.82/mm2) were also higher than group F, but was not higher than group G (18.73±3.39/mm2)(P>0.05), and there were no statistical diference in group E and in group G (P>0.05).③In no infarction region, The capillary densitiy in myocardial infarction region were higher in group E (20.11±3.98/mm2), group F(18.67±2.35/mm2), group G(20.68±3.05/mm2) than in group D (8.21±1.18)(P<0.05), but there were no statistical diference among group E、group F and groupG.(4)The comparison of infarct size:the infarct size of group E (25.23±4.79%), group F (31.41±2.59%), group G (28.95±2.52%) was smaller than that of group D (35.67±5.22%)(P<0.05), and the infarct size of group E was smaller also than that of group F, and was smaller also than that of group G (P<0.05). There were no statistical diference between group F and group G (P>0.05).Conclusion:1.EPCs in peripheral blood were mobilized and increased by Fluvastatin、 erythropoietin(EPO) and Qi Shen Yi Qi extractum in AMI rats. And these drugs can increase the capillary densitiy in myocardial infarction region and perim infarction region and no infarction region.2. These drugs can diminish infarct size, that could be the consequence of the neovascularization and the improving of microcirculation in myocardial infaction region.3.These drugs can improve the survival rate of AMI rats.