Abstract: Objective To explore the optimal condition for the differentiation of rat bone marrow mesenchymal stem cells(MSCs) into cardiomyocyte-like cells in vitro by using DMSO.Methods SD rat MSCs were isolated from rat bone marrow and cultured, then induced by 1.0%DMSO for 24 h. The cultured cells were observed under phase-contrast microscope. The immunohistochemical technique and laser scanning confocal microscope (LSCM) were used for detecting the expression of desmin, α-sarcomeric actin and C-TnT. The ultrastructures were viewed with transmission electron microscopy.Results MSCs induced by DMSO could be identified by the positive staining for Desmin, α-Sarcomeric Actin and C-TnT.The number of cells stained positively in the 1.0% was visually larger than that of other groups. Transmission electron microscope showed that paralleled myofilaments and a lot of rough endoplasmic reticulum were formed. Conclusion MSCs could be induced to differentiate into cardiomyocyte-like cells by DMSO.

Key words: marrow mesenchymal stem cells, dimethyl sulfoxide, cardiomyocytes, Rat