TH and Parkinson disease: In the nervous system of NDO rats, the expression of several neuronal markers (namely CRF, GAD2, NF200, TH, VAChT, and VGLUT) was found to be generally downregulated, due to denervation associated with SCI, MMC, and PD, the latter more evident in the substancia nigra and ventral tegmental area [40,47,49,64,73,74].