Adhesion‑Dependent Modulation of Macrophage K+ Channels
Integrin‑mediated adhesion of monocytes not only triggers cell rolling and diapedesis, it also activates ionic permeability changes resulting in monocyte activation, maturation and differentiation. Mononuclear phagocytes possess voltage‑dependent inwardly rectifying K+ (Kir) currents and delayed outwardly, rectifying K+ (Kdr) currents that are modulated by tissue origin, adherence, presence of growth factors or cytokines and the functional or differentiation state of the cells. This chapter reviews the exploration of Kir and Kdr channels in mononuclear phagocytes over the last 30 years with an emphasis on culturing conditions, modulation by substrates and role in macrophage function. It has only been recent that successful attempts have been made to study these K+ currents in monocytes/macrophages as they may be engaged in the human body which may serve as the foundation for the development of novel therapeutic agents targeting macrophage Kir/Kdr channel activity to favorably influence risk factors for hypertension, atherosclerosis and diabetes.