[The fermentation diagnosis and histologic studies in blood and the liver of surviving rats after 1 and 2 administrations of a median toxic dose of parathion methyl. 2. Tyrosine aminotransferase and pathologico-morphological findings in the liver].

Tyrosine-amino transferase, an enzyme induced to the liver via glucocorticoids, caused clearly measurable activity rises in either sex, 24 hours after 1 and 2 applications. Increased levels continued to recordable from males on the 3rd day from application, whereas enzyme activities in females had already returned to normal by that time. Histological examination of liver sections, following 1 and 2 applications of parathion methyl (PM), revealed the tissue pattern of clearly manifest toxic hepatosis with detectable mesenchymal reactions. Histologically detectable damage reached its maximum on the 2nd and 3rd days from application. Sex-related differences were not recordable. Damage in response to the 2nd application was characterised by faster mesenchymal activation and higher frequency of cell necroses. The morphological picture of the liver was rated as having returned to normal, 14 days after 1 and 2 applications of PM. These results should not be interpreted as evidence to the involvement of specific, non-cholinergic mechanisms in the processes of damage observed. The alterations might rather be attributed to unspecific disorders in the energy balance or to the effect of "stress" during intoxication.