Figure 2

Neuropathology in the rabbits treated with 2.5 μg/kg Stx2 (H&E staining). (A) The lower segment of the lumbar spinal cord showed extensive necrotic infarction in the gray matter at the onset of severe paraplegia. (B) Higher magnification of ischemic lesions in the panel (A), small vessels with fibrin-like thrombi (Th), degenerated vessels (dV), and microscopic hemorrhage (mH) were observed. (C) Nerve roots of the rabbit with ataxic gate showed microvascular thrombi and microscopic hemorrhage. Some nerve fibers were swollen and/or degenerated. In contrast to the spinal cord, (D) microscopic hemorrhage (arrows) were scattered in the brain parenchyma. At a later stage, neurons in the basal ganglia showed atrophy, darkly stained cytoplasm (E), and in the hippocampus some pyramidal neurons morphologically showed apoptotic changes with shrunken cytoplasm and apoptotic bodies (arrows) (F). (Original magnification: (A) 5.2×; (B) 250×, (C) and (D) 100×, (E) and (F) 400×.)