S1PR2 and Hyperammonemia: The aims of this work were: )1) assess if hyperammonemia increases the content of IL-17 and membrane expression of its receptor in cerebellum of hyperammonemic rats; (2) identify the cell types in which IL-17 receptor is expressed and IL-17 increases; (3) assess if blocking IL-17 signaling with anti-IL-17 ex vivo reverses activation of microglia and astrocytes and TNFα-TNFR1-S1PR2-CCL2-BDNF-TrkB pathways in cerebellum of hyperammonemic rats.