Simulating The Cardiac Microenvironment In Vitro To Observe The Effects Of Cardiac Microenvironment On The Differentiation Of Bone Marrow Mesenchymal Stem Cells Into Myocardial-like Cells

ObjectiveWe simulated the cardiac microenvironment in vitro to observe the effects of cardiac microenvironment on the differentiation of bone marrow mesenchymal stem cells(MSCs) into myocardia1-1ike cells ,and compare the promoting effect with inducer 5-azacytidine(5一aza)MethodsMyocardial cells isolated from newly born wister rats were lysed by repeat freezing and defrosting。MSCs isolated from adult wister rats were cultured in four different systems。Medium A:control medium:ordinary medium。Medium B:medium with 5-aza。Medium C:medium with 5-aza and myocardial cell freeze thawing liquid medium。Medium D: with myocardial cell freeze thawing liquid medium。The dynamic changes of MSCs morphology in different media were observed。The immunocytochemical technique was used for the expression of Troponin T(cTnT),Connexin43,α—Sarcomeric Actin and CD31。With light microscope,selecting eight unoverlap visual fields。Image analysis computed the rate of positive cells。Data analysis adopted 13.0 statistics software。Measurement datas indicated ( x±s)。Making T-test with every two medium。P<0.05 have statistics meaning。Result①Simulating the cardiac microenvironment in vitro:The origin cultivation myocardial cell for seven days can form the group of cell or cell monolayer,to spread the foot of the blttle with concentric circles or peak valley。The group of the cell have visible synchronism。②The inducing conclusion of MSCs in vitro:after one week,5-aza medium most of cells growns with rod shape, at equal pace spread tightly, with big volume。myocardial cell freeze thawing liquid medium have the trend of aggregation growth,to form a great quantity daughter cells,it is clearly to see the architectonic of actin filament-like。medium with 5-aza and myocardial cell freeze thawing liquid medium have the ablating cells more less than 5-aza medium, to see the architectonic of actin filament-like,a part of cells can form fat vacuolus。③The conclusion of the immunocytochemical technique:induce the cells after one week,A system expressedα—Sarcomeric Actin。B system expressed Troponin T(cTnT) ,α—Sarcomeric Actin,and Connexin43,the positive rate is 20%,28%,25%。D system expressed Troponin T(cTnT),α—Sarcomeric Actin,and Connexin43,the positive rate is 23%,32%,28%。The rate of positive of D system is higher than B system and C system(p<0.05)。C system expressed Troponin T(cTnT),α—Sarcomeric Actin,and Connexin43,the positive rate is 21%,28%,24%,There is no obviously contrast with B system(P>0.05) C system and D system were expressed CD31。Conclution①Simulating the cardiac microenvironment in vitro by adding myocardial cell freeze thawing liquid can high performance induce MSCs into myocardia1-1ike cells.②A part of MSCs can expressed CD31, it can induce bone marrow mesenchymalstem cells(MSCs) into vascular endothelial cells.Compared with 5-aza, myocardial cell freeze thawing liquid medium can offer a physical environment for myocardium regeneration。...