AQP4 and amyotrophic lateral sclerosis: For instance, the expression of two channels found on astrocytic endfeet, the inward rectifier-type potassium channel family member, KCNJ10, and the water channel, AQP4, is affected in opposite ways in animal ALS models, where KCNJ10 levels are decreased whereas AQP4 levels are increased [55,56,74,75,76].