Atypical tubule hyperplasia and renal tubule tumors in conventional rats on 90-day toxicity studies.

Journal Article (Journal Article;Multicenter Study)

Bilateral, multicentric renal tubule tumors were found in 4 rats at the termination of 3 separate 90-day toxicity studies during the safety evaluation of 3 unrelated chemicals. The 3 studies were conducted at 2 separate locations, but the rats used were obtained from the same commercial source. The rat strains were Fischer-344 (1 male and 1 female case) and Sprague-Dawley (2 female cases). Three of the renal tumor cases were from either the high-dose or mid-dose treatment groups, and 1 case was an untreated control. The tumors were accompanied by multiple foci of atypical tubule hyperplasia but only in the tumor-bearing rats. There were no lesions associated with renal tumor pathogenesis in any of the remaining treated or untreated animals in the 3 studies. In addition, there was no indication of nephrotoxicity in the treated or untreated animals. Tumor morphology was characterized by a generally vacuolated appearance, eosinophilia, cytoplasmic and nuclear pleomorphism, and conspicuously hypertrophied nucleoli. The renal tubule tumors in these 90-day studies were compared to hereditary renal tubule tumors occurring in the Eker rat, a Long-Evans derivative with a genetic predisposition to this tumor type. The multiplicity of renal tubule tumors, early age of onset, and tumor morphology described in the cases from the 90-day studies were very similar to those characterizing the hereditary renal tumor model.(ABSTRACT TRUNCATED AT 250 WORDS)

Full Text

Duke Authors

Cited Authors

  • Hard, GC; Long, PH; Crissman, JW; Everitt, JI; Yano, BL; Bertram, TA

Published Date

  • 1994

Published In

Volume / Issue

  • 22 / 5

Start / End Page

  • 489 - 496

PubMed ID

  • 7899777

International Standard Serial Number (ISSN)

  • 0192-6233

Digital Object Identifier (DOI)

  • 10.1177/019262339402200503


  • eng

Conference Location

  • United States