INDUCTION BY X-IRRADIATION OF ADENOSINE TRIPHOSPHATASE-DEFICIENT ISLANDS IN THE RAT-LIVER AND THEIR CHARACTERIZATION

  • 1 January 1985
    • journal article
    • research article
    • Vol. 45  (12) , 6078-6082
Abstract
The potential of X-rays to induce preneoplastic lesions in the rat liver was studied in order to clarify the reason why X-rays are ineffective in inducing hepatocellular carcinoma in this animal. Male newborn rats at 8 or 22 days of age received whole body X-ray irradiation of 100 to 400 rads. After weaning they were fed either basal diet or a diet containing 0.05% phenobarbital as a promoter. X-rays induced nuemrsou adenosine triphosphatase-deficient islands appearing in the liver by wk 22 of age. However, they were generally small, .gamma.-glutamyl transpeptidase-negative, and did not clearlyr espond to the promopting stimulus of phenobarbital. No hepatic tumors were observed y 22 mo. after radiation, even in phenobarbital-treated animals. Thus the X-ray-induced enzyme-altered islands differ somewhat qualitatively from those induced by potent hepatic carcinogens and their preneoplastic potential if at all present may be very low. Similarities between these X-ray-incuded lesions and some types of spontaneously enzyme-altered islands are pointed out.