EFFECT OF EXTRACELLULAR-MATRIX ON PC-12 CELL-SHAPE AND DOPAMINE PROCESSING

Substrates of various origins can affect the morphology, growth and functional properties of many cell types. PC 12 cells (a clonal line of rat pheochromocytoma) synthesize, store and secrete dopamine as well as other transmitters. These cells are rounded and loosely attached when cultured on plastic, but flatten and spread extensively when cultured on an extracellular matrix secreted by bovine cortical endothelial cells. Spontaneous dopamine release into culture medium was significantly higher from cells which were flattened on matrix, and the cellular content of dopamine was less than in cells which were maintained on plastic. The higher levels of medium dopamine in matrix cultures were not due to an increase in cellular attachment or growth as determined by [3H]thymidine incorporation. A variant of PC 12 cells which is flat on plastic showed no change in cell shape or dopamine release when plated on matrix. Extracellular matrix apparently promotes a change in cell shape, and this change in the physical arrangement of these cells alters their release and storage of dopamine.