BK channels have been implicated in a variety of physiological processes ranging from regulation of smooth muscle tone to modulation of hormone and neurotransmitter release. Interestingly, BK channels are also involved in modulating K+ transport in the mammalian kidney and colon epithelium with a potential role in the hyperkalemic phenotype observed in patients with familial hyperkalemic hypertension type 2, and in the pathophysiology of hypertension. In addition, BK channels are responsible for resting and stimulated Ca2+-activated K+ secretion in the distal colon.
Hv1 channels have been detected in many cell types, including macrophages, blood cells, lung epithelia, skeletal muscle and microglia. These channels have a central role in the phagocytic system. In macrophages, Hv1 channels participate in the generation of reactive oxygen species in the respiratory burst during the process of phagocytosis.