The lipoprotein lipase activity in cultured beating heart cells of the post-natal rat.

Summary The lipoprotein lipase (LPL) activity was studied in cultured beating heart cells of the post natal rat as a function of the culture age, from the freshly trypsinized cell suspension up to the 14th day of culture. The LPL activity remains at a practically stationary level during the first four days of culture, and then increases rapidly to reach a plateau, at a level 3–4 times higher at the 21th day of culturing. The significance of this enzymatic activity progression comparing to 3H thymidine incorporation from the point of view of cell differentiation is discussed. Our results suggest that after the 12th day of culture, cells contain their optimal enzymatic apparatus for lipid met…