Steroid hormones,through their receptors known as nuclear receptors,play a crucial role in the brain function and structure.To regulate transcription,NRs are required to bind to cofactors known as coactivators,among such coactivators,the members of the P160 family,or steroid receptor coactivators (SRCs),are essential for NR-mediated transcriptional regulation.The SRC gene family contains three members (SRC-1,2,and 3),which serve as transcriptional coactivators for nuclear receptors and certain other transcription factors.Studies have shown that SRC-1 is the most abundant distributed in the brain,SRC-1 null mice exhibit moderate motor dysfunction and delayed development of cerebellar Purkinje cells,suggesting a crucial role of SRC-1 in the brain.To further address the role that SRC-1 plays in the brain,we studied its dictribution in th femal mice brain using immunohistochemical technique.