Figure 1: pCPCs can be cultured and expanded. Growth rate comparison between 6 different cell lines derived from atrium and ventricle of 3 individual mice age 3, 4 and 6 months. pCPCs from the atrium (A1, A2,and A3) cultured in expansion medium began to proliferate after day 7th and expanded beyond 40 days but not the cells from ventricle (V1, V2,and V3), which did not grow well.