at PENNSYLVANIA STATE UNIV on March 6, 2014cpt.sagepub.comDownloaded from Homeostatic Role of Toll-like Receptor 4

cated in the development of atherosclerosis in mice. In the current study, we have identified a new role for TLR4 in the maintenance of endocrine function within the endothelium. Specifically, we found that endothelium-dependent dilator responses in vessels from TLR4-/- mice were greatly reduced despite a mor-phologically normal appearance. In addition, we found evidence of significant left ventricular dilation in the hearts of TLR4-/- mice. Importantly, we found that endothelium-dependent dilator responses in vessels from TLR2-/- mice remained intact