Endocrine System

Thyroid Gland, Follicular Cell - Hypertrophy

    Narrative
    Thyroid Gland, Follicular Cell - Hypertrophy in a male F344/N rat from a subchronic study. Focal hyperplasia is present in two adjacent follicles (arrows).
    Thyroid Gland, Follicular Cell - Hypertrophy in a male F344/N rat from a subchronic study. Higher magnification of Figure 1 shows the epithelium lining the follicles is cuboidal to columnar.
    Thyroid Gland, Follicular Cell - Hypertrophy in a male F344/N rat from a subchronic study. The cuboidal to columnar lining epithelium contains small, clear, cytoplasmic vacuoles.
    Thyroid Gland, Follicular Cell - Hypertrophy in a female Sprague-Dawley rat from a chronic study. Follicles are smaller than normal, are lined by cuboidal epithelium, and contain amphophilic, flocculant-appearing material and exfoliated epithelial cells.

    Authors

    Robert R. Maronpot, DVM, MS, MPH, DACVP, DABT, FIATP
    Senior Pathologist
    Experimental Pathology Laboratories, Inc.
    Research Triangle Park, NC

    Amy Brix, DVM, PhD, DACVP
    Senior Pathologist
    Experimental Pathology Laboratories, Inc.
    Research Triangle Park, NC

    Reviewers

    Thomas J. Rosol, DVM, PhD, DACVP
    Professor of Veterinary Biosciences
    Senior Advisor, Life Sciences, Technology Commercialization and Knowledge Transfer
    The Ohio State University
    Columbus, OH

    Susan A. Elmore, MS, DVM, DACVP, DABT, FIATP
    Staff Scientist, NTP Pathologist
    NTP Pathology Group
    National Toxicology Program
    National Institute of Environmental Health Sciences
    Research Triangle Park, NC