2.3- dinor-thromboxane

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...

Figure 6.7 Urinary 2,3-dinor-thromboxane (Tx) (O—O) and 2,3-dinor-6-keto-prosta-...

Figure 6.9 Urinary, 2,3-dinor-thromboxane (Tx) B2 and plasma 11-dehydro-thromboxane B2 (inset) following administration of streptokinase (SK), 750 000—1 500 000 units intravenously, in patients with acute myocardial infarction. The shaded area represents the range of urinary 2,3-dinor-thromboxane B2 levels observed in patients with acute myocardial infarction not receiving thrombolytic therapy n = 12). The solid area on the y-axis is the range in healthy volunteers. Ml, myocardial infarction not receiving thrombolytic therapy...

Lawson, J.A., Brash, A.R., Doran, J. and FitzGerald, G.A. (1985). Measurement of urinary 2,3-dinor-thromboxane B2 and thromboxane B using bonded-phase phenylboronic acid columns and capillary gas chromatography-negative-ion chemical ionization mass spectrometry. Anal Biochem., 150, 463-470... 

Thromboxane A2 has a plasma half-life as short as 7 s (48) and spontaneously decomposes non-enzymatically to the functionally inactive TXBg, which is either excreted unaltered or as one of several other metabolites. For example, TXBg can undergo /3-oxidation to dinor-TXB2. 

Benigni A, Chiabrando C, Piccinelli A, Perico N, Gavinelli M, Furci L, Patino O, Abbate M, Bertani T, Remuzzi G. Increased urinary excretion of thromboxane B2 and 2, 3-dinor-TxB2 in cyclosporin A nephrotoxicity. Kidney Int 1988 34 164-174. 

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