Figure 2.

Dual-channel confocal laser scanning microscope photomicrographs comparing the distribution of 3β-HSD and GABA_A receptor β₂/β₃ subunit-like immunoreactivity in the frog hypothalamus. (A–C) Frontal section through the posterior tuberculum labeled with the antiserum against 3β-HSD revealed with DAR_S/TXR (A; arrows) or the monoclonal antibody against the β₂/β₃ subunits revealed with GAM_S/Alexa-488 (B; arrowheads). Combination of the two images acquired in A and B revealed the presence of β₂/β₃ subunit-like immunoreactivity in a subset of 3β-HSD-positive neurons (C; arrows). (Bars = 10 μm.) (D–F) Frontal section through the nucleus of the periventricular organ labeled with the antiserum against 3β-HSD revealed with DAR_S/TXR (D) or the monoclonal antibody against the β₂/β₃ subunits revealed with GAM_S/Alexa-488 (E). Combination of the two images acquired in D and E revealed the coexistence of 3β-HSD- and β₂/β₃ subunit-like immunoreactivity in the same neuron (F). (Bars = 2 μm.)