Moreover, the treatment of SMA mice with Y-27632 and Fasudil did not induce an increase in the number of surviving motoneurons, suggesting that the beneficial effects of ROCK inhibitors are most likely on improving the health and function of the remaining motoneurons, but not on preventing the SMN-dependent NMJ denervation and subsequent axonal and neuronal loss. This evidence concerns the gene SMN1 and proximal spinal muscular atrophy.