NTRK1 and amyotrophic lateral sclerosis: The addition of ROCK inhibitor Y27632 and the addition of CHIR99021 on top of the increment of NT-3 on the medium (protocol C compared to protocol A’, Fig. 4A and Fig. S2), induced in healthy and ALS cells a decrease of NTRK1 (p < 0.05) and an increase in PVALB (p < 0.05).