TNF and rheumatoid arthritis: In the present study, we used TNF-Tg mice to identify the cellular source of iNOS expression in efferent lymphatic vessels from inflamed joints, the role of LEC-produced iNOS in inhibition of LSMC function, and the effects of NO inhibitors (Nω-nitro-l-arginine methyl ester [l-NAME] and l-N6-(1-iminoethyl)lysine 5-tetrazole-amide [l-NIL]), as well as ferulic acid (FLA; the active component of an herbal therapy for RA [33, 34]), on LEC-mediated LSMC inhibition, lymphatic dysfunction, and joint pathology.