Quantitative cytophotometric analysis of brain neuronal RNA and protein changes in acute T-2 mycotoxin poisoned rats.
Male Sprague-Dawley rats (200 g) injected intraperitoneally with T-2 toxin, a trichothecene mycotoxin protein synthesis inhibitor, at dosages of 0.75, 1.0, 1.5 and 6.0 mg/kg (1 LD50 = 0.9 mg/kg) were decapitated at 8 hr post-exposure. Data were obtained on changes in neuronal (perikaryal) RNA levels, protein contents and nucleolar volumes in cerebrocortical (layer III) and striatal (caudate-putamen) brain regions using quantitative azure B-RNA and Coomassie-protein cytophotometry and ocular filar micrometry. Correlative observations were made on changes in brain cytomorphology. Reductions in neuronal RNA/protein contents and nucleolar volume were used as indices of impaired perikaryal functioning. At 8 hr after T-2 toxin poisoning the following results were obtained in cerebrocortical and striatal brain compartments: neuronal RNA contents were generally maintained at control values in both brain regions, however, moderate RNA depletion was evidenced in the cerebral cortex with 1.5 mg/kg T-2 and in the striatum with a 6.0 mg/kg dose; neuronal protein levels were suppressed in a dose-dependent fashion within the cerebrocortex, while in the striatum there was no direct correspondence between protein loss and T-2 dosage; neuronal nucleolar volumes were typically maintained at control levels in both neuronal compartments. Microscopic observations revealed no gross evidence of T-2-induced brain cytopathology. These data indicate that T-2 toxin does not elicit direct cytopathic actions in these two brain regions, thus indicating that cerebrocortical and striatal compartments do not represent primary target sites of T-2 toxicant action.(ABSTRACT TRUNCATED AT 250 WORDS)
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D003592:Cytophotometry; D008297:Male; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D009474:Neurons / Q000378:metabolism*; D012313:RNA / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains; D012717:Sesquiterpenes / Q000506:poisoning*; D013605:T-2 Toxin / Q000506:poisoning*
D009419:Nerve Tissue Proteins; D012717:Sesquiterpenes; D012313:RNA; D013605:T-2 Toxin