SOD1 and amyotrophic lateral sclerosis: Our data identified that (1) C-bouton evolution exhibits different temporal profiles in WT and SOD1 Mns, (2) M2 receptors present a complex dynamic in C-bouton PSM in WT Mns that is completely disrupted in SOD1 Mns, (3) lamina X cholinergic interneurons are more abundant in high lumbar segments in SOD1 mice compared to WT, (4) these neurons are subjected to neurodegeneration in the SOD1 ALS model and (5) early C-bouton alterations have no physiological impact on cholinergic neuromodulation of newborn Mns.