Cyclo-oxygenase inhibition

V.c.1.1. Cyclo-oxygenase inhibition. Inhibition of cyclo-oxygenase reduces the level of circulating prostaglandins and neurogenic inflammation. This is the mechanism of action of nonsteroidal antiinflammatory drugs (NSAID) and aspirin. The mode of action of paracetamol is less clear (inhibition of prostaglandins in the nociceptors of the posterior horn of the spinal cord and action on the supraspinal structures implicated in nociception). 

Cyclo-oxygenase inhibition. Ethanol (100%) extract and essential oil of the aerial parts were active, ICjf, 6.7 mg/L and 7.5 mg/ L, respectively . 

Cyclo-oxygenase inhibition. Methanol extract of the ether-insoluble fraction of the fresh seed, administered to rats at a dose of 100 p,g/mL, inhibited platelets by 46%. Methanol extract of ether-soluble fraction inhibited platelets by 29% " . 

Complement classical pathway inhibition. Ethyl acetate and methanol extracts of the fresh leaf were active on red blood cells, IC50 greater than 7.7 pg/mL and greater than 5.8 pg/mL, respectively " ". Cyclo-oxygenase inhibition. Essential oil of the unripe fruit, at a concentration of 100 pg/mL, produced weak activity on platelets " . 

Cyclo-oxygenase inhibition. Ethanol (95%) extract of the dried fruit, administered to sheep, was active on microsomes, IC50 28.1... 

PG promote free water excretion, probably by acting at several different sites. Cyclo-oxygenase inhibition with NSAID should, therefore, diminish... 

The decrease in RBF and GFR produced by cyclo-oxygenase inhibition is more pronounced in the anaesthetized than the conscious animaP " . During anaesthesia, there are increased levels of circulating vasoconstrictor hormones, such as angiotensin II and catecholamines, which would require an increase in vasodilatory PG in order to counteract the expected renal vasoconstriction . There are no comparable studies in anaesthetized humans. 

Moroney MA, Alcaraz MJ, Border RA, Carey F, Hoult JR. Selectivity of neutrophil 5-lipoxygenase and cyclo-oxygenase inhibition by an anti-inflammatory flavonoid glycoside and related aglycone flavonoids. J Pharm Pharmacol 1988 40 787-792. 

In the rat retina, ischemia upregulates expression of the neuronal nitric oxide synthase and cyclo-oxygenase-2 these effects can be effectively inhibited by lutein (Choi et al., 2006). 

Unfortunately, frequent exposure to NSAIDS may also cause two detrimental effects. These agents inhibit the activity of cyclo-oxygenase, an important enzyme in synthesis of gastroprotec-tive prostaglandins. More importantly, NSAIDS may cause breaks... 

Parsadaniantz, S. M. et al. Effects of the inhibition of cyclo-oxygenase 1 or 2 or 5-lipoxy-genase on the activation of the hypothalamic-pituitary-adrenal axis induced by interleukin-lbeta in the male Rat. J. Neuroendocrinol. 12, 766, 2000. 

S. Khare, S. Cerda, R. K. Wall, F. C. von Lintig, M. Tretiakova, L. Joseph, D. Stoiber, G. Cohen, K. Nimmagadda, J. Hart, M. D. Sitrin, G. R. Boss and M. Bissonnette, Ursodeoxycholic acid inhibits Ras mutations, wild-type Ras activation, and cyclo-oxygenase-2 expression in colon cancer, Cancer Res., 2003, 63, 3517. 

Indometacin, which is a non-steroidal anti-inflammatory drug, inhibits the enzyme cyclo-oxygenase implicated in inflammatory reactions. Indometacin is more effective as an anti-inflammatory agent than ibuprofen and tends to have a higher side-effect profile, including headache, diarrhoea and gastrointestinal disturbances. Rectal administration reduces but does not prevent gastrointestinal tract disturbances. 

Naproxen, a non-steroidal anti-inflammatory drug, inhibits prostaglandin release through inhibition of the cyclo-oxygenase-2 enzyme, producing an analgesic and anti-inflammatory effect. 

Davies, N. M. Clinical pharmacokinetics of nabumetone. The dawn of selective cyclo-oxygenase-2 inhibition , Clin. Pharmacokinet. 1997, 33, 404-416. 

Costa, B., Conti, S., Giagnoni, G. et al. Therapeutic effect of the endogenous fatty acid amide, palmitoy-lethanolamide, in rat acute inflammation inhibition of nitric oxide and cyclo-oxygenase systems. Br. J. Pharmacol. 2002 137 413-20. 

Laughton, M.J., Evans, P.J., Moroney, M.A., Hoult, J.R.S., and Halliwell, B. 1991. Inhibition of mammalian 5-lipoxygenaseand cyclo-oxygenase by flavonoids and phenolic dietary... 

Santicioli P, Carganico G, Meini S et al. (1995) Modulation of stereoselective inhibition of cyclo-oxygenase of electromechanical coupling in the guinea pig isolated renal pelvis. Br J Pharmacol 114 1149-1158... 

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