Changes in the development of Experimental Autoimmune Prostatitis (EAP) bycastration in aged rats

During Experimental Autoimmune Prostatitis (EAP). 12-month-old rats show a higher cellular autoimmune response and lower humoral autoimmune response a gainst prostatic components than 3-month-old rats subjected to the same ant igen stimulus. We analyzed if thymus recovery by orchidectomy could affect the development of EAP in 12-month-old rats. Thirty days after gonadectomy, 12-month-old rats showed an increment in the thymic mass and in the thymoc ytes absolute number, with percentages of the four main cell subpopulations (defined by CD4-CD8 molecules expression) similar to the 3-month-old rats. The DTH response of castrated 12-month-old with EAP were diminished in com parison with sham-castrated 12-month-old rats with EAP, resembling the valu es observed in 3-month-old rats with EAP. The prostates of castrated 12-mon th-old rats with EAP did not show inflammatory mononuclear cell infiltratio n, as did control 3- and 12-month-old rats with EAP. Castration seems to mo dulate negatively EAP in 12-month-old rats, possibly through the regenerati on of thymus after testosterone deprivation. (C) 2000 Elsevier Science Ltd. All rights reserved.