Human aortic endothelial cells ( HAECs ) were stimulated by angiotensin II ( Ang II , @ nmol/L ) with or without pretreatment of valsartan ( @ nmol/L ) , and relative expression of cyclooxygenase-@ ( COX-@ ) and thromboxane B @ ( TXB @ ) and both p@ mitogen-activated protein kinase ( p@MAPK ) and nuclear factor-kB ( NF-kB ) activities were assessed .