NTRK2 and Parkinson disease: In both mouse and rat intrastriatal 6-OHDA lesion PD models a pre-lesion, 60-day treadmill exercise increased and hence partially normalized the striatal tissue levels of proBDNF, BDNF and its receptor TrkB, increasing striatal tissue BDNF level by 33% in PD animals compared with non-exercised PD animals, measured by western blot, accompanied by parallel behavioral improvements (Tuon et al., 2012, 2014).