Fig. 4.

Surgical and chemical castration enhanced thymic mass and restored thymic architecture. (A) Thymic mass decreased with age. Mass increased after either surgical or chemical castration. (B) This difference was quantified and confirmed a significant increase in thymic weight (*P < 0.01; **P < 0.001 versus 12-month normal; ^P < 0.01 versus 2-month normal; n=3 to 5 animals per group). This improvement in thymic mass was associated with a restoration of the normal thymic architecture as seen in (A) by the recovery of corticomedullary differentiation that had been disrupted in the noncastrated 12-month-old animal (H&E staining, ×100). C, cortex; M, medulla.