Structure-function relationship of the action of T-2 toxin on bovine platelets

The effect of the trichothecene mycotoxin, T-2 toxin, on the ultrastructure of bovine platelets was investigated. In both toxin-treated and untreated platelets, the ultrastructure of the resting bovine platelet was characterized by the absence of an extensive open canalicular system and the appearance of granules and vacuoles which frequently impinged on the outer platelet membrane. No major ultrastructural changes were produced by T-2 toxin under conditions in which the platelet aggregation response was significantly inhibited. In bovine platelets exposed to the toxin, as in untreated platelets, there is evidence of pseudopod formation, indicating that T-2 toxin does not impair the initial response of platelets to stimulation. This observation is consistent with the companion function study which showed that, while T-2 toxin can impair both the rate and extent of aggregate formation, the most dramatic change is the relative instability of the platelet aggregates that form in the presence of the toxin.