Open AccessImpairment of Coronary Endothelial Function by Hypoxia-Reoxygenation Involves TRPC3 Inhibition-mediated KCa Channel Dysfunction: Implication in Ischemia-Reperfusion Injury
Author(s) -
Xiang-Chong Wang,
Wentao Sun,
Jie Fu,
Junhao Huang,
CheukMan Yu,
Malcolm J. Underwood,
GuoWei He,
Qin Yang
Publication year - 2017
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/s41598-017-06247-3
Subject(s) - trpc3 , bradykinin , trpc , endothelial dysfunction , chemistry , vasodilation , transient receptor potential channel , hypoxia (environmental) , endocrinology , medicine , endothelium , electrical impedance myography , trpc1 , pharmacology , receptor , organic chemistry , oxygen
Despite increasing knowledge of the significance of calcium-activated potassium (K Ca ) and canonical transient receptor potential (TRPC) channels in endothelial physiology, no studies so far have investigated the link between these two distinct types of channels in the control of vascular tone in pathological conditions. We previously demonstrated that hypoxia-reoxygenation (H-R) inhibits endothelial K Ca and TRPC3 channels in porcine coronary arteries (PCAs). The present study further investigated whether modulation of TRPC3 is involved in H-R-induced K Ca channel inhibition and associated vasodilatory dysfunction using approaches of wire myography, whole-cell voltage-clamp, and coimmunoprecipitation. Pharmacological inhibition or siRNA silencing of TRPC3 significantly suppressed bradykinin-induced intermediate- and small-conductance K Ca (IK Ca and SK Ca ) currents in endothelial cells of PCAs (PCAECs). TRPC3 protein exists in physical association with neither IK Ca nor SK Ca . In H-R-exposed PCAECs, the response of IK Ca and SK Ca to bradykinin-stimulation and to TRPC3-inhibition was markedly weakened. Activation of TRPC3 channels restored H-R-suppressed K Ca currents in association with an improved endothelium-derived hyperpolarizing factor (EDHF)-type vasorelaxation. We conclude that inhibition of TRPC3 channels contributes to H-R-induced suppression of K Ca channel activity, which serves as a mechanism underlying coronary endothelial dysfunction in ischemia-reperfusion (I-R) injury and renders TRPC3 a potential target for endothelial protection in I-R conditions.