Photomicrographs of the morphological characterization of apoptotic motoneurons. A-C: Photomicrographs of TUNEL and ChAT double immunohistochemical stained section at 2 mm rostral from the epicenter removed at 24 h post-SCI. A: lower magnification of the ventral gray matter; B: higher magnification corresponding to the frame in A; C: high magnification corresponding to the frame in B. Two enlarged TUNEL-positive motoneurons were shown in the frames of C. Scale bar, 100 μm. D-F: Photomicrographs of TUNEL and ChAT double immuno-fluorescence stained section at 2.05 mm rostral to the epicenter removed at 24 h post-SCI. The section was double immuno-stained with anti-ChAT primary antibody (D, red) and TUNEL (E, blue), followed by anti-mouse Alexa Fluor 594 secondary antibody. F: immuno-colocalization of D and E showing apoptotic motoneurons (bluish red) in the ventral gray matter of the cord from a vehicle control rat. Photomicrographs are taken at high magnification (scale 100 μm).