6-ketoprostaglandin-f1-alpha and Thrombocythemia--Essential

Essential thrombocythaemia (ET) is characterised by enhanced platelet generation and thrombosis. Once daily (od) aspirin incompletely inhibits platelet thromboxane (TX)A2 production in ET. A twice daily (bid) dosing is necessary to fully inhibit TXA2. Whether this dosing regimen affects in vivo prostacyclin (PGI2) biosynthesis is unknown. PGI2 biosynthesis was characterised in 50 ET patients on enteric-coated (EC) aspirin 100 mg od, by measuring its urinary metabolite, 2,3-dinor-6-keto-PGF1α (PGI-M). Moreover, in a crossover study 22 patients poorly responsive to standard aspirin based on serum TXB2 levels (≥4 ng/ml) were randomised to different seven-day aspirin regimens: EC aspirin 100 mg od, 100 mg bid, 200 mg od, or plain aspirin 100 mg od. PGI-M measured 24 hours after the last aspirin intake (EC, 100 mg od) was similar in patients and healthy subjects both on (n=10) and off (n=30) aspirin. PGI-M was unrelated to in vivo TXA2 biosynthesis, and not affected by EC aspirin 100 mg bid or 200 mg od as compared to EC 100 mg od. PGI2 biosynthesis in aspirin-treated ET patients appears unrelated to TXA2 biosynthesis, and not affected by an improved aspirin regimen, demonstrating its vascular safety for future trials.

Topics: 6-Ketoprostaglandin F1 alpha; Aged; Aspirin; Blood Platelets; Clinical Protocols; Drug Dosage Calculations; Epoprostenol; Female; Humans; Male; Middle Aged; Platelet Aggregation; Thrombocythemia, Essential; Thromboxane A2

To observe the influence of the plasma thromboxane B2 (TXB2), 6-keto-PGF1alpha, CD62P and PAC-1 and Thrombus in patients with primary thrombocytosis (ET). To observe the effect of sodium ozagrel to prevent and treat thrombosis in patients with ET.. The subjects including 48 patients with ET. All patients were measured the plasma TXB2, 6-keto-PGF1alpha, CD62P and PAC-1 before and after treatment with or without sodium ozagrel.. The plasma levels of CD62P, PAC-1, TXB2, 6-keto-PGF1alpha and TXA2/PGI2 in the patients with ET were significantly higher than the normal people (P < 0.01). The levels of CD62P, PAC-1, TXB2, TXB2/6-keto-PGF1alpha in patients with treatment of sodium ozagrel were higher than patients without treatment of sodium ozagrel (P < 0.01). The plasma levels of CD62P, PAC-1 and TXA2/PGI2 in patients with treatment of sodium ozagrel and that in normal people had no significant distinction (P < 0.01). All the index of conventional therapy group were higher than normal people (P < 0.01) but had no significant distinction with the patients before conventional treating. The incidence of thrombus in patients treated with sodium ozagrel was lower than patients treated without sodium ozagrel (P < 0.05).. With the treatment of sodium ozagrel in patients with ET, the CD62P, PAC-1, TXB2 and TXA2/PGI2 of plasma could be decreased. And the incidence of thrombus was decreased.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Antibodies, Monoclonal; Blood Platelets; Female; Humans; Male; Methacrylates; Middle Aged; P-Selectin; Receptors, Fibrinogen; Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; Thrombocythemia, Essential; Thrombosis; Thromboxane A2; Thromboxane B2

We have evaluated the arachidonic acid (AA) metabolism in patients with myeloproliferative disorders (MPD). In essential thrombocythemia (ET), the generation of thromboxane B2 was found significantly reduced and inversely correlated with platelet count. Polycythemia vera (PV) patients showed an increased formation of this metabolite of AA. Prostaglandin E2 and 6-keto-PGF1 alpha generation were markedly reduced in patients with chronic myelogenous leukemia. Our study confirms that the arachidonate metabolism is frequently deranged in patients with MPD. The opposite changes in thromboxane formation in ET and PV could be one of the factors responsible for the different incidences of thrombotic and hemorrhagic complications in these diseases.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Aged; Arachidonic Acid; Arachidonic Acids; Bleeding Time; Dinoprostone; Female; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukocyte Count; Male; Middle Aged; Myeloproliferative Disorders; Platelet Count; Polycythemia Vera; Primary Myelofibrosis; Thrombocythemia, Essential; Thromboxane B2