Boris Yagen

T-2 toxin effect on cultured myocardial cells.

Beat rate, contractility and viability of cultured myocardial cells perfused with solutions containing various concentrations of T-2 toxin were studied. While doses below 50 micrograms/ml had no immediate effect, those above 250 micrograms/ml decreased beat rate and amplitude. After 10-30 min of perfusion most cells stopped beating and did not restart after withdrawal of toxin. Nevertheless, most cells remained viable as judged by morphology and trypan blue exclusion. A 24-h exposure to doses of 5 or 2.5 micrograms/ml of toxin decreased the beat rate and inotropic responses of the myocytes. After 48 h cell death ensued. Thus T-2 toxin has some direct toxicity to myocardial cells but the lethal dose seems too high to make this the cause of cardiovascular failure.

Cardiovascular pathology induced by passive transfer of splenic cells from syngeneic rats treated with T-2 toxin

Mononuclear cells were separated from spleens and lymph nodes of Lewis rats treated 5 weeks previously with repeated small doses of T-2 toxin or solvent only. The cells from each site were then injected intraperitoneally into 4 groups of syngeneic Lewis rats. The animals injected with spleen cells from T-2 toxin-treated donors developed marked cardiovascular changes which were similar to those due to T-2 toxin itself. Rats injected with lymph node cells as well as those given each kind of cell from solvent-treated donors showed only occasional mild vascular changes. The changes seen after splenic cell transfer may be due to superinduction of interleukin 2 by T-2 toxin.