Endocrine System

Parathyroid Gland - Hyperplasia, Focal

    Narrative
    Parathyroid Gland - Hyperplasia, Focal in a male F344/N rat from a chronic study. This low-magnification photomicrograph contains a focus of hyperplasia (arrow) with a growth pattern distinct from the adjacent parathyroid parenchyma.
    Parathyroid Gland - Hyperplasia, Focal in a male F344/N rat from a chronic study. Focal hyperplasia is characterized by cells with rounded nuclei and abundant hypertrophic cytoplasm but without compression of adjacent parathyroid parenchyma.
    Parathyroid Gland - Hyperplasia, Focal in a male Wistar Han rat from a chronic study. Two focal areas of hyperplasia with pale, enlarged cells (compared with surrounding parathyroid parenchyma) are present.
    Parathyroid Gland - Hyperplasia, Focal in a male F344/N rat from a chronic study. Two to three adjacent nests of hyperplastic foci are present; the pale staining of their hypertrophic cells makes them stand out from the normal parathyroid tissue.

    Authors

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

    Georgette D. Hill, D.V.M., Ph.D.
    Toxicologic Pathologist/Assistant Pathology Program Manager
    Comparative Molecular Pathology Division
    Integrated Laboratory Systems, 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

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