calcimycin and 14-15-episulfide-eicosatrienoic-acid

An 'epoxygenase' eicosanoid analog, 14, 15-cis-episulfide-eicosatrienoic acid, has several unique pharmacological effects on platelets. These include (i) inhibition of ionophore A23187- but not thrombin-induced activation, (ii) inhibition of thromboxane B2 biosynthesis derived from endogenous but not exogenous arachidonic acid, and (iii) attenuation of ionophore-mediated increases in cytosolic Ca2+ when extracellular or membrane Ca2+ is available but not when these pools are excluded. Neither elevation of cyclic AMP levels, a potent inhibitory process, nor direct antagonism of the prostaglandin H2/thromboxane A2 receptor is responsible for the actions of 14, 15-cis-episulfide-eicosatrienoic acid. These properties distinguish 14, 15-cis-episulfide-eicosatrienoic acid from other antiaggregatory substances.

Topics: 8,11,14-Eicosatrienoic Acid; Blood Platelets; Calcimycin; Calcium; Collagen; Cyclic AMP; Humans; Intracellular Fluid; Platelet Activation; Platelet Aggregation; Platelet Aggregation Inhibitors; Thrombin; Thromboxane B2