Inflammation chronic, nitric oxide role

Nitric oxide has a role in both acute and chronic inflammation. NOS-3 is involved in the vasodilation associated with acute inflammation. In experimental models of acute inflammation, inhibitors of NOS-3 have a dose-dependent protective effect, suggesting that nitric oxide promotes edema and vascular permeability. Nitric oxide has a detrimental effect in chronic models of arthritis dietary L-arginine supplementation exacerbates arthritis whereas protection is seen with NOS-2 inhibitors. Psoriasis lesions, airway epithelium in asthma, and inflammatory bowel lesions in humans all demonstrate elevated levels of nitric oxide and NOS-2. Synovial fluid from patients with arthritis contains increased oxidation products of nitric oxide, particularly peroxynitrite. 

Laroux FS, Lefer DJ, Kawachi S, Scalia R, Cockrell AS, Gray L, Van der Heyde H, Hoffrnan JM and Grisham MB, Role of nitric oxide in the regulation of acute and chronic inflammation. Antioxid Redox Signal 2(3) 391-6,2000. 

Much evidence suggests that chronic inflammation is closely related to colon carcinogenesis. Thus, factors involved in chronic inflammation are of great interest as targets of cancer chemopreventive agents. Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) are abxmdantly expressed in the epithelium of colitis and colon cancer cells and appear to play an important role in colon carcinogenesis (J-4),... 

Ying, L. and Hofseth, L.J. (2007). An emerging role for endothelial nitric oxide synthase in chronic inflammation and cancer. Cancer Res. 67(4), 1407-1410. 

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