Distribution of Cre activity in additional brain sites. A, fluorescent photomicrograph showing βGalactosidase immunoreactivity (βGal-ir) in the cerebral cortex (layers 2–3 and 5–6) of a female mouse from line J2-4. B, darkfield photomicrograph showing the distribution of Kiss1 mRNA in the cerebral cortex (layers 2–3 and 6) of a C57BL/6 female mouse. C, brightfield photomicrograph showing the hybridization signal (silver grains) of Kiss1 riboprobe at cellular level (arrows), in the layers 2–3 of the neocortex. Observe the absence of hybridization signal in the layer 1. D–F, fluorescent photomicrographs showing Cre activity (Kiss1 reporter mice, green fluorescent protein immunoreactivity/GFP-ir) in the lateral septum (LS, D), in the anterodorsal preoptic nucleus (ADP, E), and in the medial nucleus of the amygdala (MeA, F). Abbreviations: 3v, third ventricle; ac, anterior comissure; CPu, caudate putamen; ic, internal capsule; LV, lateral ventricle; MS, medial septum; opt, optic chiasm. Scale bar: A–B = 400 μm, C = 10 μm, D–F = 200 μm.