6-ketoprostaglandin-f1-alpha and indobufen

We evaluated the effectiveness of indobufen administration in reducing neutrophil activation in a clinical model of ischemia-reperfusion. Thirty stable patients with intermittent claudication due to occlusive peripheral arterial disease of the leg were randomly assigned to two groups. Patients in group I were treated with indobufen [200 mg orally twice daily (p.o. b.i.d.) for a week]; patients in group II received a placebo. Both groups of patients were submitted to standardized treadmill exercise until onset of claudication. Plasma levels of thromboxane B2 (TxB2) and 6-keto-prostaglandin F1alpha(6-k-PGF1alpha) neutrophil filterability, and neutrophil activation (by nitro-blue tetrazolium test) were assessed in blood samples from the femoral vein draining the ischemic leg. The values were obtained at rest and 5, 30, and 60 min after onset of claudication. Urinary albumin excretion was measured at rest and 1 h after onset of claudication. Plasma levels of TxB2 and 6-k-PGF1alpha increased significantly in the placebo group 5 min after onset of claudication, whereas only a slight nonsignificant increase was observed in the indobufen-treated group at the same timepoint.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Aged; Arterial Occlusive Diseases; Cyclooxygenase Inhibitors; Humans; Intermittent Claudication; Isoindoles; Lactic Acid; Middle Aged; Neutrophil Activation; Phenylbutyrates; Platelet Aggregation Inhibitors; Thromboxane B2

Interest in the antithrombotic potential of low-dose aspirin is based on its ability to inhibit thromboxane (Tx)A2-related platelet function with concomitant sparing of vascular prostacyclin (PGI2) production. The aim of this study was to investigate the effect of low-dose aspirin (20 mg daily for 7 days) on the increase in fibrinolytic activity in healthy volunteers after venous occlusion. We also tested the effect of high-dose aspirin (650 mg X 2), of salicylate (569 mg X 2) and of indobufen (200 mg X 2), a new cyclo-oxygenase inhibitor unrelated to salicylates. Low-dose aspirin reduced serum TxB2 generation by about 90% and suppressed arachidonate-induced platelet aggregation. In contrast, fibrinolytic activity, measured by the euglobulin lysis area and the euglobulin lysis time, was not significantly affected. Both high-dose aspirin and indobufen significantly inhibited TxB2 generation and the rise in fibrinolytic activity induced by venous occlusion, without affecting the pre-occlusion values. Salicylate did not significantly affect any parameter studied. Besides offering a favorable solution to the "aspirin dilemma" related to the TxA2/PGI2 balance, low-dose aspirin might leave intact the fibrinolytic capacity of the vessel wall.

Topics: 6-Ketoprostaglandin F1 alpha; Analysis of Variance; Aspirin; Fibrinolysis; Hematocrit; Humans; Isoindoles; Phenylbutyrates; Thrombosis; Thromboxane B2