Fig. 1.

Representative brain images from pigs that underwent sham surgery or HI injury. a, b Macrophotographs show the anterior and posterior levels of the putamen where viable, injured, and apoptotic profiles were counted. Photos are grayscale images of hematoxylin and eosin (H&E)-stained sections that were taken at 10× magnification. Brain section orientation is indicated at the lower right of each image. c H&E-stained putamen in a sham-operated normothermic pig. Arrows denote morphologically viable neurons. Perineuronal, pericapillary, and parenchymal neuropil integrity appears excellent at this resolution. d H&E-stained putamen in an HI normothermic pig. The arrows identify morphologically ischemic necrotic neurons, which were classified as “injured” for the analysis. Neuropil integrity is severely damaged as evidenced by the overt perineuronal, pericapillary, and parenchymal vacuoles. e H&E-stained putamen in a sham-operated hypothermic pig. Arrows denote apoptotic profiles. The neuropil appears finely vacuolated with some pallor. The inset at lower right demonstrates an apoptotic profile at higher magnification (from upper right hatched box) for better visualization of spherical chromatin clumps in the nucleus. f Representative TUNEL+ profile in a sham-operated hypothermic pig. The morphology of the DNA fragmentation and compartmentation seen as round aggregates is consistent with apoptosis. The cell size suggests that this apoptotic profile is a neuron. c–d were taken at 400× magnification. f was taken at 600× magnification with oil immersion. Scale bar is 10 μm.