Fig. 4.

Expression of ERβ1 and ERβ2 in the brainstem. A: Atlas image of midbrain provides neuroanatomical context for ERβ1 (B) and ERβ2 (C) localization, respectively. B, C: Inset in the upper left corner is a lower magnification view of the region from which the larger image was taken. ERβ1 is found in a periventricular cluster of cells adjacent to the anterior pole of nucleus lateralis valvulae (nlv), whereas ERβ2 is broadly distributed throughout the periaqueductal gray (PAG). D: ERβ2 is also strongly expressed in a few cells in the periventricular layer (Pe) of the auditory division of the torus semicircularis (TS, see A for reference). E: Atlas image showing vocal motor nucleus (VMN) and vocal pacemaker neurons (VPN). F, G: Both ERβ1 and ERβ2 are expressed in VMN motor neurons and periventricular cells along the fourth ventricle (IV), as well as in the vagal motor nucleus (Xm). Three fluorescent insets in G highlight more robust nuclear ERβ2 staining of motor neurons in females and type II males compared to type I males (confirmed by qPCR, see Fig. 6). Scale bar in A represents 500 μm in A; 400 μm in E; 100 μm in B,C,F,G, and insets of G. Scale bar in the inset of B represents 200 μm for inset images in B,C,F. A and E modified from Forlano et al. (2010). Other abbreviations: ll, lateral lemniscus; MLF, medial longitudinal fasciculus.