Murine thymic androgen receptors

Studies in mice indicate that sex hormones influence the immune system. In general females are more immunocompetent than males and the administration of androgens can suppress antibody formation in females. New Zealand Black (NZB) mice manifest a lack of sex difference in the production of certain autoantibodies and the failure of androgen administration to suppress these antibody levels. To further analyze this phenomenon, androgen receptors were studies in the thymus of NZB and a non-autoimmune strain (C57Bl/6). Specific thymic androgen receptors were found in both NZB and C57Bl/6 mice. The dissociation constant and concentration of specific dihydrotestosterone receptors was determined in thymic cytosol by Scatchard plot analysis. There were no substantial differences in the binding parameters between sexes and between strains. In conclusion, both autoimmune and control strains have similar high affinity thymic androgen receptors. Therefore, the immune androgen insensitivity observed in NZB mice is not the result of a lack of high affinity thymic androgen receptors.