Prostaglandins 15-keto

Release of markers bound to the endothelial cell such as thrombomodulin is indicative of vascular damage. Increased levels of soluble thrombomodulin in plasma are diagnostic (93). Other endothelium-derived markers such as 6-keto-prostaglandin F a, which is a metabolite of prostacyclin, are useful in the assessment of endothelial function, with lower levels indicative of inability to synthesize this marker due to defective or damaged endothelium through plaque formation (93). 

Uyama O, Nagatsuka K, Nakabayashi S, Isaka Y, Yoneda S, et al. 1985. The effect of a thromboxane synthetase inhibitor, OKY-046, on urinary excretion of immunoreactive thromboxane B2 and 6-keto-prostaglandin El alpha in patients with ischemic cerebrovascular disease. Stroke 16 241-244. 

Patients with chronic renal impairment because of diminished renal prostaglandin production may also be at increased risk of NSAID-induced renal failure. NSAID-induced acute kidney injury has been documented in patients with asymptomatic, but mild chronic renal failure, defined as a recruitment serum creatinine between 133 pmol/L and 265 pmol/L (1.5 and 3.0 mg/dl) [45]. Baseline excretion of urinary prostaglandin and 6-keto-prostaglandin F was quantitatively lower in the individuals who developed NSAID-induced renal decompensation than in those who did not. Upon initiation of ibuprofen, urinary prostaglandin excretion fell in all patients, but trough concentrations were quantitatively lower in the subset of patients who experienced acute kidney injury. 

In an in vitro study using rat gastric tissue, researchers showed that an extract of 10 mg of dried comfrey leaves (S. officinale) homogenized in 1 mL of Kreb s solution increased the release of prostaglandin F2a and 6-keto-prostaglandin Fla (Stamford and Tavares, 1983). As numerous... 

There is little information on prostaglandin formation by human cardiac tissue, most of which, based on measurements of thromboxane B2, prostaglandin E2 and 6-keto-prostaglandin in aortic and coronary sinus blood, is likely to be highly artifactual. In a recent experiment, Nowak and coworkers infused radiolabelled arachidonic acid into the coronary arteries of male volunteers 3 days following a single dose of aspirin, 600 mg, by which time cyclo-oxygenase activity in endothelial cells, but not in platelets, would... 

Figure 6.5 Percent change in thromboxane A2 and prostacyclin biosynthesis, measured as excretion of their urinary metabolites, 2,3-dinor-thromboxane (Tx) 82 and 2,3-dinor-6-keto-prostaglandin (PG) respectively, in response to a thromboxane A2/prostaglandin endoperoxide receptor antagonist (L636,499) alone and in combination with a thromboxane synthase inhibitor (U63,557A) in the chronic canine model of coronary thrombosis. (Note that occlusion did not occur in dogs treated with the combination therapy)...

Figure 6.6 Urinary 2,3-dinor-thromboxane (Tx) B2 and 2,3-dinor-6-keto-prostaglandin (PG) and plasma II-dehydro-TxB2 (inset) before and following exercise-induced myocardial ischaemia in patients with stable coronary artery disease...

Chen, L.S., Ito, T., Ogawa, K., Shikano, M. and Satake, T. (1984). Plasma concentrations of 6-keto-prostaglandin Fj, thromboxane B2 and platelet aggregation in patients with essential hypertension. ]pn. Heart ]., 25, 1001-1009... 

Kuklev, D. V., J. A. Hankin et al. 2013. Major urinary metabolites of 6-keto-prostaglandin F2alpha in mice. 54(7) 1906—1914. 

Fenwick L, Jones RL, Naylor B, Poyser NL, Wilson NH Production of prostaglandins by the pseudopregnant rat uterus, in vitro, and the effect of tamoxifen, with the identification of 6-keto-prostaglandin F as a major product. Br J Pharmac (59) 191-199,... 

Rosenkranz, B., Fischer, C., Reimann, L, Weimer, K.E., Beck, G., Frolich, 3.C. Identification of the major metabolite of prostacyclin and 6-keto-prostaglandin Fj in man. Biochim. Biophys. Acta, in press... 

PACE ASCIAK CR Deuterium isotope dilution method for the specific measurement of 6-keto-prostaglandin by mass fragmentography. 

Yui Y, Hattori R, Takatsu Y, Nakajima H, Waka-bayashi A, Kawai C, Kayama N, Hiraku S, Inagawa T, Tsubojima M et al (1984) Intravenous infusion of a selective inhibitor of thromboxane A2 synthetase in man influence on thromboxane B2 and 6-keto-prostaglandin FI alpha levels and platelet aggregation. Circulation 70 599-605... 

Quantitative Determination of 6-Keto Prostaglandin in Biological Fluids by Capillary Gas Chromatography-Chemical Ionization Mass Spectrometry J. Chromatogr. 221(2) 361-366 (1980) CA 94 152848m... 

The method hereind described corresponds to that reported by Wubert et al. (32). Plasma and urine samples were collected in vials containing 0.01% butylated hydroxytoluene to prevent oxidation, immediately frozen and stored at -20°C until analysis. Samples are spiked with 2.0 ng of pH4]ll-dehydrothromboxane B2, 0.2 ng of [ H3]2,3-dinor-6-keto-prostaglandin Fia, and 2.0 ng of [ H4]prostaglandins E2, D2, and p2a as internal standards in ethanolic solution. To this was added 0.5 mL of 2-propanol. As tetradeuterated standards of isoprostanes are not commercially available at present, [ H4]prostaglandin p2a serves as a substitute internal standard for its stereoisomeric isoprostanes. A... 

Coen, P.M., P.M. Cummins, YA. Bimey, R. Devery and P.A. Cahill, 2004. Modulation of nitric oxide and 6-keto-prostaglandin F (lalpha) production in bovine aortic endothelial cells by conjugated linoleic acid. Endothelium J. Endothel. Cell Res. 11, 211-220. 

Gaudet, R. J., Levine, L., 1980 Effects of unilateral common carotid artery occlusion on levels of prostaglandins D2, F2a and 6-keto-prostaglandin Fla in gerbil brain. Stroke 11, 648-652. 

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