Figure 2.

COX-1 mRNA localization. Lower (top row) and higher (middle row) magnification dark-field images of sections through comparable levels of forebrain showing COX-1 mRNA in the brain parenchyma and in CNS blood vessels from rats killed 1 h after intravenous injection of saline (left) or LPS (2 μg/kg; right). Labeling associated with vessels is indicated by arrows (top) or asterisks (middle). Note also evenly scattered small grain clusters over the parenchyma, presumably corresponding to glial labeling, which is more salient in LPS-treated rats. Bottom row, Bright-field photomicrographs showing concurrent localization of COX-1-IR (brown) and COX-1 mRNA signal (black silver grains). COX-1-immunoreactive cells in both the parenchyma (presumed microglial; left) and vessels (right) are overlain (arrowheads) by COX-1 mRNA signal, further supporting specificity of immunolocalization. ac, anterior commissure; CP, caudoputamen; lv, lateral ventricle; lot, lateral olfactory tract; OT, olfactory tubercle. Scale bars: top row, 400 μm; middle row, 200 μm (scale bar in the middle right panel applies to top two rows); bottom row, 25 μm.