The experimental timeline depicts the cross-sectional time course design highlighting specific time-points at which select cohorts are treated and sacrificed (A). Time course in gray (Days 0-42) shows sacrifice times for non-lesioned animals treated with saline or AMI. Structures dissected at these times are indicative of the trophic response elicited by saline or AMI treatment in intact animals. Time course in black (Days 0-30) depicts sacrifice times post-lesion for animals treated with saline or AMI. Structures dissected at these times are indicative of the trophic response elicited by saline or AMI in the degenerating nigrostriatal system. Representative map detailing the interconnectivity between dissected structures of interest (B). Abbreviations: AMI=amitriptyline hydrochloride, D=day, Sac=sacrifice, 6OHDA=6-hydroxydopamine, IHC=immunohistochemistry, ELISA=enzyme-linked immunosorbent assay, STR=striatum, HIPP=hippocampus, SN=substantia nigra, FCX=frontal cortex, ACC=anterior cingulate cortex, PIR=piriform cortex