Figure 2

Expression of MHCI-HC in the primary visual cortex as revealed by in situ hybridization. A) Autoradiographs of visual cortices processed for in situ hybridization. Sections represent the main stages of visual cortex development. The expression of MHCI-HC in the 7 days-old animal (PD7) decreases with progressing age (compare with 7 months-old animal, PM7). Primary visual cortex (V1) is delineated with white dashed lines. Layer IV and subcortical white matter are delineated with white lines. Abbreviations: Postnatal day, PD; postnatal month, PM; primary visual cortex, V1; secondary/prestriate visual cortex, V2; subcortical white matter, SWM; layer IV, IV. Scale bar: 1 mm. B) Upper row: Toluidine-blue stained section of a 7 days-old animal (left) after in situ hybridization, and autoradiograph of the same section (middle panel; film autoradiography) reveal MHCI-HC signals in layers I and IV-VI of the primary visual cortex and in the subcortical white matter (SWM). Emulsion autoradiography (right) reveals silver grains clustered over single cells (arrowheads). Middle row: Toluidine-blue stained section of a 1-month old animal (left) after in situ hybridization and autoradiograph of the same section (middle panel) revealed MHCI-HC signals in all cortical layers and in the subcortical white matter (SWM). Emulsion autoradiography (right) reveals silver grains clustered over single neurons (arrowheads). Bottom row: Sense probe revealed only background signals (left; film autoradiograph) and background levels of silver grains in emulsion autoradiography (right). Roman numerals denote cortical layers. Scale bar for film autoradiographs: 1 mm. Scale bar for emulsion autoradiography: 20 μm. Abbreviations: Postnatal day, PD; postnatal month, PM; primary visual cortex, V1; subcortical white matter, SWM.