u 46619

U-46619是一种有效的TXA2激动剂，是一种血栓素A2类似物（内过氧化物），有诱导肌球蛋白轻链9 (Myl9)基因缺失小鼠主动脉平滑肌(SM)收缩的功能。

CI-930作为一种PDE-III抑制剂，具有广谱活性。它通过双重机制发挥抗聚集作用：一方面增加cAMP含量，另一方面选择性抑制血小板中TXA2的合成。CI-930能够抑制由AA、U-46619、ADP、胶原和PAF引起的血小板聚集，其IC50值分别为0.91、0.73、2.12、2.35和7.15 mumols L。

(±)11-HDHA is an autoxidation product of docosahexaenoic acid (DHA) in vitro. It is also produced from incubations of DHA in rat liver, brain, and intestinal microsomes. DHA is metabolized to 11(S)-HDHA by human platelets and canine retina. In addition to 11(S)-HDHA, 14(S)-HDHA is also produced by platelets. 11(S)-HDHA was shown to be an inhibitor of U-46619-induced human platelet aggregation and rabbit and rat aortic smooth muscle contraction with IC50 values of about 50, 4.7, and 7.5 μM, respectively. (±)11-HDHA is a potential marker of oxidative stress in brain and retina where DHA is an abundant polyunsaturated fatty acid.

8-iso PGE2 is one of several isoprostanes produced from arachidonic acid during lipid peroxidation. It is a potent renal vasoconstrictor in the rat. 8-iso PGE2 inhibits U-46619 or I-BOP-induced platelet aggregation with IC50 values of 0.5 and 5 μM, respectively. When infused into the renal artery of the rat at a concentration of 4 μg/kg/min, 8-iso PGE2 decreases the GFR and renal plasma flow by 80% without affecting blood pressure.

8-iso-13,14-dihydro-15-keto Prostaglandin F2α (8-iso-13,14-dihydro-15-keto PGF2α) is a metabolite of the isoprostane, 8-isoprostane (8-iso PGF2α), in rabbits, monkeys and humans. 8-iso PGF2α is a PG-like product of non-specific lipid peroxidation. In both humans and monkeys, exogenously infused 8-isoprostane is converted primarily to metabolites having 2 or 4 carbon atoms removed from the top side chain by β-oxidation. A similar pattern is observed when tritiated 8-isoprostane is infused into rabbits. Early in the infusion (within 10 minutes) 8-iso-13,14-dihydro-15-keto PGF2α was a significant component of the metabolite profile, which was comprised mostly of dinor 8-isoprostane metabolites. 8-iso-13,14-dihydro-15-keto PGF2α weakly inhibits the U-46619 or collagen-induced aggregation of human platelets, although a number of the E-series isoprostanes are much more potent in this assay.

TPα and TPβ are two isoforms of the human TP receptor, the G protein-coupled receptor (GPCR) that mediates the actions of thromboxane A2 (TXA2). Although their distinct physiological functions have not been fully elucidated, TPβ is believed to be responsible for vascular endothelial growth factor-induced endothelial cell differentiation and migration whereas TPα appears to be the predominant isoform expressed in platelets. CAY10535 is a TP receptor antagonist that shows ~20-fold selectivity for TPβ (IC50 = 99 nM) relative to TPα (IC50 = 1,970 nM) in the inhibition of U46619-mediated Ca2+ mobilization. This compound exhibits relatively poor activity on platelets (IC50 = 985 nM) when inhibiting U-46619-induced platelet aggregation.

Adrenomedullin (13-52) is a truncated form of adrenomedullin (1-52) . It induces nitric oxide-dependent relaxation of and inhibits release of angiotensin II and endothelin-1 from isolated rat aorta. In vivo, adrenomedullin (13-52) decreases mean arterial pressure (MAP) in spontaneously and renal hypertensive rats in a dose-dependent manner. Adrenomedullin (13-52) (10-3,000 ng per animal) reverses increases in lobar arterial pressure induced by U-46619 in a dose-dependent manner in cats but has no effect on basal lobar arterial pressure or systemic arterial pressure. It also potentiates inflammatory edema and neutrophil accumulation in rats.

(±)17-HDHA is an autoxidation product of docosahexaenoic acid in vitro. It is also produced from incubations of DHA in rat liver, brain, and intestinal microsomes. 17(S)-HDHA could be produced by enzymatic oxidation of DHA using soybean lipoxygenase (LO) and is the putative product of mammalian 15-LOs. 17(S)-HDHA was shown to be an inhibitor of U-46619 -induced rabbit and rat aortic smooth muscle contraction with IC50 values of 4.9 and 7.2 μM, respectively. (±)17-HDHA is a potential marker of oxidative stress in brain and retina where DHA is an abundant polyunsaturated fatty acid.

13(R)-HODE is the opposite enantiomer of the 13(S)-HODE produced when linoleic acid is incubated with soybean lipoxygenase. The presence of 13(R)-HODE in the supernatants and membranes of cultured bovine endothelial cells has been attributed to COX metabolism. 13(R)-HODE is a weak (IC50 = 2.7 μM) inhibitor of U-46619-induced platelet aggregation.

(±)13,14-EDT是一种氧脂和腎上腺酸的代谢产物，通过细胞色素P450（CYP）途径形成。在50 nM的浓度下，它能激活分离的大鼠冠状小动脉平滑肌细胞中的大导电钙激活钾通道（KCa1.1/BK），并导致分离的猪小动脉扩张（EC50 = 12 pM）。(±)13,14-EDT还能使用TP受体激动剂U-46619预收缩的分离牛冠状动脉放松。

(±)16,17-EDT，一种经由细胞色素P450 (CYP) 途径形成的腺苷酸代谢物和氧脂肪酸，能够诱导分离的猪小动脉舒张（EC50 = 11 pM）。此外，(±)16,17-EDT 亦能促进以TP受体激动剂U-46619 预收缩的分离牛冠状动脉的松弛。