The role of (E)-4-hydroxy-2-nonenal in platelet activation by low density lipoprotein and iron.

(E)-4-Hydroxy-2-nonenal (HNE) is a highly reactive product of the oxidation of low density lipoprotein (LDL) which increases the platelet aggregation response to various agonists. HNE formation was increased during the enhanced platelet aggregation to thrombin, ADP. A23187 and epinephrine in the presence of LDL.

The effect of cholesterol oxidation products on human platelet aggregation.

The cholesterol oxidation products (oxysterols) cholest-3,5-diene-7-one, cholestan-5 alpha, 6 alpha-epoxy-3 beta-ol (cholesterol 5 alpha-epoxide), cholestan-5 beta, 6 beta-epoxy-3 beta-ol (cholesterol 5 beta-epoxide), cholest-5-ene-3 beta-ol-7-one (7-ketocholesterol), cholest-5-ene-3 beta, 7 alpha-diol (7 alpha-hydroxycholesterol), cholestan-3 beta, 5 alpha, 6 beta-triol (cholestane triol), and cholest-5-ene-3 beta, 26-diol (27-hydroxycholesterol) potentiated platelet aggregation and increased thromboxane A2 formation in platelets challenged with thrombin, ADP or collagen. These effects were observed at oxysterol concentrations in the range 5-100 microM. Cholesterol 5 beta-epoxide and 7-ketocholesterol increased the mobilization of 3H-arachidonic acid from prelabelled platelet phospholipids in response to thrombin and collagen.

Dipyridamole inhibits the oxidative modification of low density lipoprotein.

The oxidative modification of low density lipoprotein (LDL) is believed to play an important role in the initiation of the atherosclerotic lesion. Dipyridamole, which is used clinically as a coronary vasodilator and an antiplatelet agent, has antioxidant properties. Probucol is a lipid-lowering agent which inhibits the oxidative modification of LDL.

Abnormal platelet reactivity in men with premature coronary heart disease.

Background: Continuous platelet aggregation does not occur in patients with stable coronary heart disease (CHD). However, there may be a latent potential for increased aggregation given appropriate stimuli, since increased in-vitro platelet aggregation appears to be predictive of cardiac events. This study evaluates the relationship between in-vitro platelet aggregation and coronary artery disease (CAD) as defined by angiography.

Relationship of blood cholesterol and apoprotein B levels to angiographically defined coronary artery disease in young males.

Background: Coronary heart disease is mainly caused by the effects of obstruction to blood flow in the coronary arteries from discrete mural lesions that encroach into the lumen and usually occur in arteries that are involved by atherosclerosis. Even though the level of certain lipoproteins is indisputably related to the degree of this atherosclerotic involvement of the coronary arteries, the question of whether lipoproteins are also associated with the obstructive lesions remains uncertain.

Methods: This study addressed the question in 53 males (age, 44.