出版社：American Society for Biochemistry and Molecular Biology
摘要：Stimulation of rat serosal mast cells in vitro with compound 48/80, a degranulating agent, resulted in an immediate increase in binding of low density lipoproteins (LDL) to the stimulated mast cells. The increase in binding was dose-dependent and closely followed the increase in histamine release, i.e., the exocytosis of mast cell granules. It could be demonstrated that the LDL were bound to exocytosed secretory granules which remained cell-associated. During the recovery period the granule-bound LDL were internalized by the mast cells along with the granules. A single stimulation of mast cells rendered their cytoplasm to be filled with granular material showing positive staining for both apoB and neutral lipid. This change was accompanied by a 30-fold increase in the cellular content of cholesteryl esters. Thus, rat serosal mast cells possess a specific mechanism for uptake of LDL that is activated by stimuli that lead to degranulation, the result being massive uptake of LDL by stimulated mast cells during recovery from degranulation.
