Phospholipase D is activated by phorbol ester but not CSF-1 in murine bone marrow-derived macrophages

Abstract

Phospholipase D activity was measured in murine bone marrow-derived macrophages (BMM) treated with either colony stimulating factor-1 (CSF-1 or phorbol myristyl acetate (PMA) by measuring formation of phosphatidylbutanol (PtBut) in cells preloaded with n-butanol. Addition of 10−7M PMA for 15 min stimulated the amount of PtBut formed in growth arrested cells by 3-4 fold whereas no stimulation was observed with 5000 units mL−1 CSF-1 for 0.5, 2 or 15 min. Protein kinase C activity was determined in growth-arrested BMM by phosphorylation of Myristoylated Alanine-Rich C Kinase Substrate (MARCKS). PMA stimulation for 5 min increased protein kinase C activity 5-6 fold whereas CSF-1 treatment for 5 ..