[Changes in leucocytic estrogen receptor levels in patients with gynecomastia].

The number of estrogen receptor (ER) in human peripheral leucocytes in 13 men with gynecomastia were measured by radioligand binding method. The results were compared with those of 13 sex-and age-matched healthy subjects. It was found that the number of ER in leucocytes was significantly increased in gynecomastia (Rs of leucocytes were 1054 +/- 254 sites/cell). It suggested that increase of ER levels play an important role in the pathogenesis of gynecomastia.