Figure 2.

Hormone- and age-induced thymic and bone marrow involution. (A and B) Graph of thymic weight (A) and total thymocyte number (B) in ovariectomized wild-type and PRKO mice after 12 days of E + P treatment. Wild-type mice show significantly smaller thymuses than PRKO mice after P and E + P treatment. *, P < 0.01; **, P < 0.001 (C) Graph of thymic weights for wild-type and PRKO mice at 3, 11, and 24 mo of age. Thymic involution occurred equally with age in both wild-type and PRKO mice, demonstrating that age-related thymic involution is not PR dependent.