Fig. 5

OPL ultrastructure in C57BL/6J mice is affected upon the LPS challenge. Representative z-stack images of retinal sections stained with the ribbon synapse marker CtBP2 in naïve (A, C, E) and LPS-challenged (B, D, F) C57BL/6J, Tek^Cre−negTlr4^loxP/loxP and Tek^Cre−posTlr4^loxP/loxP mice, respectively. In the LPS-challenged C57BL/6J and Tek^Cre−negTlr4^loxP/loxP mice, ribbon synapses lose their characteristic shape and are less abundant in the OPL. Representative transmission electron microscopy images (×8200 magnification) obtained from naïve (G) and LPS-challenged (I) C57BL/6 J mice. Higher magnification (×20,500) of the yellow squares in G, I are shown in H, J, respectively. The LPS exposure led to alterations in the OPL ultrastructure characterized by membrane whorls, electro-lucent cytoplasm and decreased vesicle density in rod spherules. Yellow arrows and arrowheads indicate ribbon synapses and ribbons, respectively. White asterisk indicates an affected rod and red asterisks indicate membrane whorls. b Bipolar cell dendritic process; cp cone pedicle; ER endoplasmic reticulum; h horizontal cell axon tip; m mitochondrion; rcn rod cell nucleus; rs rod spherule. Scale bars: A–F 5 μm; G, I 2 μm. H, J 500 nm