Effect of n-propylthiouracil or thyroxine on arsenic trioxide toxicity in the liver of rat

Involvement of thyroid gland in the hepatotoxic manifestations of arsenic trioxide (AsIII) has been studied in rat. The effects of n-propylthiouracil (PTU) (a thyrotoxic compound) and l-thyroxine (a thyroid hormone) have been studied with reference to T3 and T4 values in the serum, arsenic concentration in the liver, Ca2+ accumulation in the liver, aspartate transaminase, alanine transaminase and bilirubin values as the indicators of liver function, histopathological observations and finally the ultrastructural studies. It is concluded that hypothyroid condition protects against AsIII toxicity. Scavenging of reactive oxygen species (ROS) that significantly contribute in AsIII toxicity, by high intracellular concentration of reduced glutathione, as a consequence of PTU treatment is proposed as the plausible protective mechanism.