Ergül BELGE, İlhan TUNCER, Güneş T. YÜREGİR

The effect of halothane on the enzymatic activity of mouse liver and erythrocyte glucose-6-phosphate dehydrogenase

The effects of repeated halothane anaesthesia on 6-10 week old male, Mus musculus albino mice weighing 29-32 g were studied. Halothane, a widely used anaesthetic, is known to be metabolised in the liver to toxic intermediates through cytochrome P4502E1 (CYP2E1). During the first week of repeated dosage, glucose-6- phosphate dehydrogenase (G6PDH) activity decreased in both erythrocytes and liver cells, and during this time, livers increased significantly in weight and suffered histopathological damage, the damage increasing with the dosage of halothane, in the range 0.25-1.0 ml twice daily. When repeated anaesthesia was continued for a second week, G6PDH activity increased significantly and histopathological damage to the liver showed no further increase. Human and mouse G6PDH show homology, and further work to examine the parameters controlling the eventual increase of enzyme activity in response to insult by halothane and its metabolites would be worth while.

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