P2RX4 and amyotrophic lateral sclerosis: Finally, given the recognised role of purinergic signalling in ALS neuroinflammatory processes [28], we demonstrated that the protein levels of purinergic receptors P2X7 (2.9 ± 0.3 compared to vehicle-treated mice) and P2Y12 (5.2 ± 1 compared to vehicle-treated mice) were significantly increased by clemastine, while not statistically significant effect was observed for P2X4 protein content (Fig. 2e).