PTGS2 and hypertensive disorder: Kuper et al demonstrated that LPS mediates enhanced Cox-2 expression in renal medullary colletion duct cells by TLR4-mediated activation of the NFkB signaling pathway.[21] In hypertension, as mentioned before, TLR4 expression is increased in the heart of SHR compared to Wistar-Kyoto rats.[6] Conversely, studies such as the one by Li et al showed that NFkB is activated in the heart, kidney and aorta in SHR compared with Wistar-Kyoto rats.[22]