Activation and proliferation signals in murine macrophages: Stimulation of Na , K ‐ATPase activity by hemopoietic growth factors and other agents

Abstract

Purified colony stimulating factor (CSF‐1) stimulates the Na+, K+‐ATPase activity of murine bone marrow‐derived macrophages (BMM) and resident peritoneal macrophages (RPM) measured as ouabain‐sensitive 86Rb+ uptake. Similar concentrations of CSF‐1 stimulate the Na+, K+‐ATPase activity and DNA synthesis in BMM whilst ouabain, a specific inhibitor of the Na+, K+‐ATPase, also inhibits this CSF‐1‐mediated DNA synthesis. Other purified hemopoietic growth factors, granulocyte‐macrophage CSF (GM‐CSF) and interleukin‐3 (IL‐3), and the tumor promoter, 12‐0‐tetradecanoyl‐phorbol‐13‐acetate (TPA), even though differing in their mitogenic capabilities, are also stimulators of the Na+,K+‐ATPase activity ..