Special Senses System

Ear, Epithelium - Hyperplasia

    Narrative
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study. There are increased layers of squamous epithelial cells with some rete peg formation is present; a large aggregate (asterisk) of cerumen and necrotic cell debris is also present.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study. There are increased layers of squamous epithelial cells with some rete peg formation is present; a large aggregate (asterisk) of cerumen and necrotic cell debris is also present.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study. The exophytic, papillary projections of squamous epithelium in the external ear canal (arrow) represent focal hyperplasia.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study. The exophytic, papillary projections of squamous epithelium in the external ear canal (arrow) represent focal hyperplasia.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study. There is a complex papillary pattern of squamous epithelial hyperplasia in the external ear canal.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study. There is a complex papillary pattern of squamous epithelial hyperplasia in the external ear canal.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study (higher magnification of Figure 3). Hyperkeratosis and chronic-active inflammation accompany the squamous epithelial hyperplasia.
    Ear, Epithelium - Hyperplasia in a male Fischer 344/N rat from a chronic study (higher magnification of Figure 3). Hyperkeratosis and chronic-active inflammation accompany the squamous epithelial hyperplasia.

    Author

    Margarita M. Gruebbel, DVM, PhD, DACVP
    Senior Pathologist
    Experimental Pathology Laboratories, Inc.
    Research Triangle Park, NC

    Reviewers

    Ruth E. Hurley, DVM, PHD, DACVP
    Senior Veterinary Pathologist
    Huntingdon Life Sciences
    North Brunswick, NJ

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