TH and Parkinson disease: The intrastriatal injection of CDNF prevents the loss of TH-positive neurons in a 6-OHDA-lesioned rat model of PD (Lindholm et al., 2007), and protected dopaminergic neurons in 6-OHDA and MPTP mouse models of PD (Lindholm et al., 2007; Voutilainen et al., 2009).