These studies try to elucidate why isocoproporphyrin appears in hexachlorobenzene-poisoned rats' feces. Chronic exposure of hexachlorobenzene to rats produces an experimental model for human porphyria cutanea tarda. After 8 weeks of treatment, rats showed high porphyrin excreta and 50% inhibition of liver uroporphyrinogen decarboxylase activity.
View Article and Find Full Text PDFIn the present study, the effects of hexachlorobenzene (HCB) on epidermal growth factor receptor (EGFR) content of liver microsomes and plasma membrane, and on EGFR-tyrosine kinase activity in the microsomal fraction were investigated. In addition, we studied the parameters of the tyrosine kinase signalling pathway such as protein tyrosine kinase (PTK) activity and phosphotyrosine content in microsomal and cytosolic protein. To determine whether the observed alterations were correlated with a manifestation of overt toxicity, a single very low dose of HCB (1mg/kg body wt) and two much higher doses (100 and 1000 mg/kg body wt), the highest being toxicologically significant in that it reduced serum thyroxine (T(4)) and inhibited uroporphyrinogen decarboxylase (URO-D) (EC 4.
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