Abstract: Objective To investigate the feasibility of the bone marrow mesenchymal stem cells (BMSCs) as the seed cells for construction of small diameter blood vessels and its induced mechanisms. Methods The bone marrow cells were obtained from hind femur and tibia of male Sprague-Dawley（SD） rats with a body weight of 100 g. The cells were purified by whole bone marrow primary culture before repeated passage in vitro amplification. Cell morphology was observed, and expressions of CD34, CD90, and CD105 cell factors were examined by flow cytometry to identify whether they were the BMSCs. Then, the BMSCs obtained were divided into the experiment group and the control group. The cells in the experiment group were induced to differentiate into the vascular smooth musclelike cells by the Dulbecco’s modified Eagle’s mediumlow glucose(DMEM-LG) plus alltrans retinoic acid and dbcAMP, while the cells in the control group were cultured by the normal DMEM-LG. We observed the morphological characteristics of the BMSCs and detected the expressions of smooth muscle-α actin (SM-α-actin), calponin, and vascular smooth muscle myosin heavy chain(SMMHC) by immunofluorescence and flow cytometry with the fifth generations cells after induction. Results The cells obtained through primary culture appeared spindleshaped and showed characteristic swirling growth. The surface marker CD34 was negative, while CD90 and CD105 were positive. After induction, the cells in the experiment group grew slowly and were slightly ovalshaped. The expression of SM-α-actin, calponin, and SMMHC was significant in the experiment group. In the control group, cell morphology and cell growth were similar to the those of BMSCs in the experiment group, but the expression of SM-α-actin, calponin, and SMMHC was negative. Conclusion The BMSCs can be induced to differentiate into the phenotype of vascular smooth musclelike cells by alltrans retinoic acid，the induced cells which can act as seed cells for tissue engineering construction of small diameter blood vessels.

Citation： HE Fengpu,WANG Liming,CHEN Wen,et al. Induction of Bone Marrow Mesenchymal Stem Cells into Vascular Smooth Musclelike Cells in Vitro. Chinese Journal of Clinical Thoracic and Cardiovascular Surgery, 2011, 18(3): 236-239. doi: Copy