Aflatoxin B1-induced changes of glutathione-S-transferase activity in the plasma and liver of the rat

Abstract

The influence of low doses of aflatoxin B1 (AFB1) and partial hepatectomy (PH) on glutathione-S-transferase (GST) activity was studied in the plasma and liver of the rat. Methods. The animals were divided into four groups. The first (I) and the second (II) group were treated with AFB1 freshly dissolved in dimethyl sulphoxide (DMSO), and administered as a single intraperitoneal dose of 50 mg/rat 24 hrs after the rats had undergone either sham operation or, 40% PH, respectively. The third group (III) of animals was treated with a total dose of 1 mg AFB1 - 5 days per week during a period of 8 weeks. The non-treated animals were used as controls (C). Results. We observed a significant increase of GST activity in the plasma of all experimental groups compared to the controls (C), (p<0.02 to p<0.005). In the liver, the GST activity of all experimental groups was also significantly increased, compared to the controls (from p<0.02 to p<0.005). Conclusion. The administration of both single and multiple doses of AFB1 led to long term increase of GST activity in the rat plasma and liver, and partial hepatectomy had no significant effect on this phenomenon.Ispitivan je uticaj niskih doza aflatoksina B1 (AFB1) i parcijalne hepatektomije (PH) na aktivnost glutation-S-transferaze (GST) u plazmi i jetri pacova. Metode. Životinje su podeljene u četiri grupe. Prva (I) i druga (II) grupa su tretirane AFB1 prethodno sveže rastvaranim u dimetilsulfoksidu (DMSO) i davanim u jednoj intraperitonealnoj dozi od 50 mg po pacovu (24 časa posle izvršene lažne operacije ili 40% PH). Treća grupa (III) bila je tretirana ukupnom dozom od 1 mg AFB1, pet puta nedeljno tokom osam nedelja. Životinje koje nisu tretirane predstavljale su kontrolnu grupu (C). Rezultati. Značajno povećanje GST aktivnosti (p<0,02 - p<0,005) u poređenju sa kontrolnom grupom, utvrđeno je i u plazmi i u jetri svih ispitivanih grupa pacova. Zaključak. Dobijeni rezultati pokazuju da jednokratna, kao i višekratna primena niskih doza AFB1 dovodi do dugotrajne indukcije aktivnosti GST u plazmi i jetri pacova, te da parcijalna hepatektomija nema veći uticaj na ovaj fenomen.nul