(Left) Darkfield digital micrographs of transverse hemisections through the lumbar spinal cords of a normal male (top), a saporin-injected male (SAP, middle), and a testosterone-treated saporin male (SAP+T, bottom), after BHRP injection into the left vastus lateralis muscle. (Right) Computer-generated composites of BHRP-labeled somata and processes 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.