Photoaffinity labelling of androgen receptors from human foreskin and cultured genital fibroblasts with tritiated methyltrienolone [3H]R1881.

Androgen receptors were partially purified by affinity chromatography of cytosols prepared from either normal foreskins or normal cultured fibroblasts. Partially purified receptors were covalently labelled with [3H]R1881 (tritiated methyltrienolone) by ultraviolet photoactivation. Gel electrophoresis of cytosols from both sources showed two peaks of specific binding, Mr approximately 40 K and approximately 85 K, under denaturing conditions. Photoaffinity labelling of the human androgen receptor may thus provide a useful tool in further studies on disorders of androgenization.