AIM To explore the roles of nitric oxide synthase (NOS), heme oxygenase (HO) and cyclooxygenase (COX) in gastric ulceration and to investigate the relationships of the expression and activities of these enzymes at different stages of gastric ulceration. METHODS Gastric ulcers (kissing ulcers) were induced by luminal application of acetic acid. Gastric tissue samples were obtained from the ulc...

the most commonly used classes of medications, accounting for 3% of all prescriptions dispensed in the U.S. About 50 million Americans receive NSAID therapy for both chronic disorders, including rheumatoid arthritis and osteoarthritis, and acute conditions such as postoperative pain, headache, tendonitis or bursitis, and dysmenorrhea. All NSAIDs inhibit the COX enzymes responsible for prostagla...

Design of selective cyclooxygenase-2 (COX-2) inhibitors is still a challenging task because of active site similarities between COX isoenzymes. To help with this issue, we tried to generate a 3D-QSAR (3 dimensional quantitative structure activity relationship) model that might reflect the essential features of COX-2 active sites. Compounds in a series of resveratrol derivatives inhibitors with ...

Recent epidemiological studies and animal experiments have demonstrated that nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the incidence of colorectal carcinoma. Cyclooxygenase (COX) is the principal target of NSAIDs. COX is the first oxidase in the process of prostaglandin production from arachidonic acid. COX enzyme may be involved in the initiation and/or the promotion of carcinogenes...

Recent epidemiological studies and animal experiments have demonstrated that nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the incidence of colorectal carcinoma. Cyclooxygenase (COX) is the principal target of NSAIDs. COX is the first oxidase in the process of prostaglandin production from arachidonic acid. COX enzyme may be involved in the initiation and/or the promotion of tumorigenesi...

Recent epidemiological studies and animal experiments have demonstrated that nonsteroidal antiinflammatory drugs (NSAIDs) reduce the incidence of colorectal carcinoma. Cyclooxygenase (COX) is the principal target of NSAIDs. COX is the first oxidase in the process of prostaglandin production from arachidonic acid. COX enzyme may be involved in the initiation and/or the promotion of carcinogenesi...

The cyclooxygenase (COX) enzyme system is the major pathway catalyzing the conversion of arachidonic acid into prostaglandins (PGs). PGs are lipid mediators implicated in a variety of physiological and pathophysiological processes in the kidney, including renal hemodynamics, body water and sodium balance, and the inflammatory injury characteristic in multiple renal diseases. Since the beginning...

Cyclooxygenase (COX; also known as prostaglandin endoperoxide synthase) is a key enzyme in the biochemical pathway leading to the synthesis of prostaglandins. A large amount of epidemiological and experimental evidence supports a role for COX-2, the inducible form of the enzyme, in human tumorigenesis, notably in colorectal cancer. COX-2 mediates this role through the production of PGE(2) that ...

n Sept. 30, 2004, the pharmaceutical giant Merck & Co. Inc. announced a voluntary worldwide withdrawal of VIOXX (rofecoxib), its arthritis and acute pain COX-2 inhibiting medication. The company’s decision was based on data from a new, three-year prospective, randomized, placebo-controlled clinical trial, which showed that after 18 months of use, VIOXX increased relative risk for confirmed card...