Metabolic modulation of potassium channels.

Recent investigations have shown that a range of small molecules that reflect the metabolic state of a cell regulate the activity of potassium channels. For instance, hydrogen peroxide has been shown to activate adenosine 5'-triphosphate-sensitive potassium channels (K(ATP) channels), whereas heme closes certain calcium-activated potassium channels. Although the exact function of the beta subunit associated with voltage-gated potassium channels is still unclear, its crystal structure suggests that membrane excitability is directly coupled to metabolism.