Perfusion system for studying peptide secretion from endocrine cells with high time resolution

To study the secretion from endocrine cells in culture, we have developed a cell column perfusion system with a time resolution of 4 s. The core of th e system is a perfusion chamber with a cell-supporting matrix of monosized polystyrene beads. The particles are solid and can withstand a high pressur e gradient without deformation. The minimum amount of cell material require d to obtain detectable levels of secretory products is a function of the as say sensitivity, perfusion flow, fraction volume and time resolution. The v olume of the perfusion chamber is therefore adjustable to satisfy varying d emands of minimum cell number. The general flow characteristics if the syst em were characterized using radiolabeled substances of various molecular si zes. Using the system in secretory studies of rat pituitary tumor (GH(4)C(1 )) cells, we have identified differences in secretion profiles that may be related to the kinetics of the different transmembrane and intracellular me chanisms involved.