Immunocytochemical localization of estrogen-binding neurons in the songbird brain.

This study used monoclonal antibodies against estrogen receptor for the identification and localization of estrogen-binding cells in the avian brain. The distribution of estrogen-binding neurons in the songbird brain conformed to the general vertebrate pattern with highest labelling in hypothalamus and preoptic area. For the first time, estrogen-binding neurons were found in the song control system: these neurons might provide a substrate for the direct action of estrogen on the song system.