Abstract: Objective  To establish a  method to separate and identify the  rat renal tubular epithelial cells (RTECs) and analyze the proliferation  ability of the obtained cells,and to provide theoretical basis and technique support for analysis experiment in vitro of kidney diseases such as  kidney injury and so on.Methods The renal tubules were separated with   type Ⅱ collagenase digestion  and purified with Percoll density gradient centrifugation and cultured in normal environment,when the RTECs grew out from the tubule,the cytokeratin-18 (CK-18) expression was detected with immunohistochemistry and the expressions of CK-18 in P0,P1 and P2 cells were detected with flow cytometry.The proliferation ability  of each generation was evaluated with CCK-8 method.Results  After cultured for 24 h,the RTECs began to grow outside from the tubule and they looked like paving road stones after cultured for 72 h.In the process of passage,the expression efficiencies of CK-18 were 95.9%,91.5%,and 76.8% in P0,P1 and P2 RTECs,and  the RTECs were dead gradually. The proliferation ability  of  P2 cells was more weaken than that of P1 cells (P<0.05),and more mixed cells existed in the culture system.Conclusion The method established in this study is cheap,credited as well as convenient.However,the cells just could be passaged for 2 times and couldn't be cultured for long time.Only the cells of P0 and P1 could be applied in analysis experiment in vitro.

Key words: renal tubular epithelial cells,
separation, identification, proliferation ability