o2- generation stimulated by opsonized zymosan or phorbol myristate acetate , by monocytes or monocyte-derived macrophages , and phagocytosis of opsonized zymosan by j774.2 macrophages , showed dependence on external na+ only if these cells had been pre-treated with nh4+ .
C0031308
phagocytosis
C0007634
cells