KCNQ5 Potassium Channel Activation Underlies Vasodilation by Tea

BACKGROUND/AIMS: Tea, produced from the evergreen Camellia sinensis, has reported therapeutic properties against multiple pathologies, including hypertension. Although some studies validate health benefits of tea, few have investigated molecular mechanisms action. The KCNQ5 voltage-gated potassium channel contributes to vascular smooth muscle tone and neuronal M-current regulation. METHODS: We applied electrophysiology, myography, mass spectrometry in silico docking determine effects their underlying tea its components on KCNQ channels arterial tone. RESULTS: A 1% green extract (GTE) hyperpolarized cells by augmenting activity >20-fold at resting potential; similar black were inhibited milk. In contrast, GTE had lesser KCNQ2/Q3 KCNQ1/E1. Tea polyphenols epicatechin gallate (ECG) epigallocatechin-3-gallate (EGCG), but not or epigallocatechin, isoform-selectively activation voltage dependence. mutagenesis revealed that ECG requires KCNQ5-R212, sensor foot. Strikingly, EGCG KCNQ-dependently relaxed rat mesenteric arteries. CONCLUSION: vasodilation tea; are candidates for future anti-hypertensive drug development.