Fig. 4. (A , B ) Light microphotograph of the transverse (1 or 30 μm) section taken from L3 spinal segment of an animal subjected to 6 min of spinal ischemia and 48 h of reperfusion. Animal received 30 μg intrathecal morphine at 30 min of reflow. Number of dark-staining α motoneurons (arrows) localized in ventral horn and in dorsal horn (A , inset , arrows; 40×) can be seen (original magnification 10×[A ], 20×[B ]. (C , D ) Light microphotograph of the transverse (30 μm) section taken from L3 spinal segment of an animal subjected to 6 min of spinal ischemia and 48 h of reperfusion. Animal received 30 μg intrathecal morphine at 24 h of reflow. Normally appearing α motoneurons and interneurons can be seen (original magnification 10×[C ], 20×[D ]).