Growing and differentiating characterization of aortic smooth muscle cell line, p53LMAC01 obtained from p53 knock out mice

Recently we have established an aortic smooth muscle cell line, p53LMAC01 o btained from p53 knockout mice. This cell line showed some differentiated p roperties which were accelerated by 5-azacytidine treatment [1]. In this st udy, further characterization of p53 LMAC01 cell line was investigated acco rding to cell growth and differentiation, and especially focused into the c hanges of cell feature, actin filaments' formation, and changes of intracel lular calcium concentrations to sympathetic nerve transmitter, norepinephri ne. While the cell feature was changed from flattened shape to extended for m during 4 days, actin filaments were developing, arranging in parallel to longitudinal direction, and gathering under the surface membrane. In 11 day s many cells died and detached from substrate, while actin filaments became poor except for the surface membrane in the remained cells. Appearance of calcium response to noradrenalin needed several days after passage as well as a morphological change of the cells for the extended form and developmen t of actin filaments. The calcium response was maintained on 11 days, which coincided with the result that the cells hold actin filaments under the su rface membrane. These results suggest that p53LMAC01 cell line maintains se veral differentiated characters of adult smooth muscle cell and that their expression needs several days after passage. (Mol Cell Biochem 190: 99-104, 1999).