Otro
ALTERED FOCI OF HEPATOCYTES IN RATS INITIATED WITH DIETHYLNITROSAMINE AFTER PROLONGED FASTING
Registro en:
Food and Chemical Toxicology. Oxford: Pergamon-Elsevier B.V., v. 31, n. 9, p. 629-&, 1993.
0278-6915
10.1016/0278-6915(93)90045-Z
WOS:A1993LX82400004
Autor
Schmitt, FCL
Estevao, D.
Kobayasi, Shoiti
Curi, P.
Decamargo, JLV
Resumen
The influence of fasting on the potential of diethylnitrosamine (DEN) to initiate liver cucinogenesis was tested in a medium-term assay using the development of putative preneoplastic altered foci of hepatocytes (AFH) as the endpoint. Male Wistar rats fasted for 48 hr were given a single ip injection of DEN (200 mg/kg body weight). Partial hepatectomies were carried out at wk 3 and the rats were killed at wk 8. Fasted rats exhibited a small increase in the numbers of AFH with glutathione S-transferase in the placental form and eosinophilic AFH when compared with non-fasted animals. However, after a 6-wk exposure to 0.05% sodium phenobarbital in the diet, there were no differences in the numbers of AFH between fasted and non-fasted animals. Fasting also increased DEN-dependent centrilobular cell necrosis and specifically drug metabolism as indicated in vivo by a decreased time of paralysis of the lower limbs induced by zoxazolamine (40 mg/kg body weight, ip) and by an unaltered sleeping time induced by sodium pentobarbital (40 mg/kg body weight, ip). The results indicate that although fasting during the initiation stage of carcinogenesis increases DEN hepatotoxicity, it does not interfere quantitatively with the development of liver preneoplastic lesions.