NTF3 and Atrophy: Thus, a similar pattern of MN dendritic atrophy occurred at 2 wpi followed by dendritic restoration at 4 wpi, irrespective of when NT-3 was given (pre- or post-injury), indicating that the NT-3 effect is mediated via promoting regrowth of atrophied dendrites rather than preventing existing dendrites from injury-induced dendritic atrophy.