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Thymus - Atrophy - Gallery

Image of atrophy in the thymus from a male Harlan Sprague-Dawley rat in a subchronic study
Thymus - Normal in a male Harlan Sprague-Dawley rat from a subchronic study. The ratio of cortex to medulla is approximately 2:1 (1:1:1, two cortices to medulla).
Image of atrophy in the thymus from a male Harlan Sprague-Dawley rat in a subchronic study
Thymus - Normal in a male Harlan Sprague-Dawley rat from a subchronic study (higher magnification of Figure 1). The lymphocytes are more numerous in the cortex than in the medulla.
Image of atrophy in the thymus from a female F344/Ntac rat in a subchronic study
Thymus - Atrophy in a treated female F344/NTac rat from a subchronic study. The cortex, showing minimal atrophy, is thinner and more irregular compared with normal (Figure 1).
Image of atrophy in the thymus from a female F344/Ntac rat in a subchronic study
Thymus - Atrophy in a treated female F344/NTac rat from a subchronic study (higher magnification of Figure 3). The cortex, showing minimal atrophy, is thinner and more irregular compared with normal (Figure 2).
Image of atrophy in the thymus from a female Harlan Sprague-Dawley rat in a chronic study
Thymus - Atrophy in a treated female Harlan Sprague-Dawley rat from a chronic study. With mild atrophy, the cortex becomes progressively thinner and the cortical-medullary junction becomes less distinct.
Image of atrophy in the thymus from a female Harlan Sprague-Dawley rat in a chronic study
Thymus - Atrophy in a treated female Harlan Sprague-Dawley rat from a chronic study (higher magnification of Figure 5). The cortex is thinner, and the cortical-medullary junction is less distinct compared with Figure 4.
Image of atrophy in the thymus from a female Harlan Sprague-Dawley rat in a chronic study
Thymus - Atrophy in a treated female Harlan Sprague Dawley from a chronic study. With moderate atrophy, delineation of the cortex and medulla is multifocally indistinct.
Image of atrophy in the thymus from a female Harlan Sprague-Dawley rat in a chronic study
Thymus - Atrophy in a treated female Harlan Sprague Dawley from a chronic study (higher magnification of Figure 7). With moderate atrophy, delineation of the cortex and medulla is multifocally indistinct.
Image of atrophy in the thymus from a female Harlan Sprague-Dawley rat in a chronic study
Thymus - Atrophy in a treated female Harlan Sprague-Dawley from a chronic study. With marked atrophy, the lack of distinction between the cortex and medulla due to lymphocyte depletion gives the thymus a more uniform appearance.
Image of atrophy in the thymus from a female Harlan Sprague-Dawley rat in a chronic study
Thymus - Atrophy in a treated female Harlan Sprague-Dawley from a chronic study (higher magnification of Figure 9). With marked atrophy, the distinction between the thymic cortex and medulla is no longer visible due to lymphocyte depletion.