Do depolarizing currents in the endothelium evoke contraction of vascular smooth muscle?

Endothelial cells release potent chemicals that dilate the blood vessels they line. Electrical coupling exists between endothelial and smooth muscle cells and this route is utilized by endothelial hyperpolarization to also produce dilation, especially in small arteries. We now hypothesize that a depolarizing current in the endothelium spreads directly to the smooth muscle to exert a novel constricting influence that we record from small arteries. This depolarizing current counteracts the hyperpolarizing current, which is reduced with age and some diseases eg diabetes, preeclampsia. We will determine the mechanisms underlying this constricting influence and thus test this exciting new concept in endothelial regulation of blood vessels.