Darkfield digital micrographs and matching computer-generated composites of transverse hemisections through the lumbar spinal cords of a sham animal (A, F), an injured animal given a blank implant (spinal cord injury [SCI]; B, G), an estradiol-treated injured animal (SCI+E; C, H), a dihydrotestosterone-treated injured animal (SCI+D; D, I), and an injured animal treated with both hormones (SCI+E+D; E, J), after BHRP injection into the left vastus lateralis muscle. Computer-generated composites of BHRP-labeled somata and processes were drawn at 480 μm intervals through the entire rostrocaudal extent of the quadriceps motor pool; these composites were selected because they are representative of their respective group average dendritic lengths. Scale bar = 500 μm.