An imbalance between the histamine regulatory function (decreased) and DA (increased via D1R) was demonstrated in the striatum of mice with congenital hyperammonemia, providing a theoretical basis for the development of aminergic wake-promoting therapeutics to treat hyperammonemic disorders (59).The D1R-H3R heteromer is expressed in the brain, and it can selectively link GABAergic neurons and MAPK signals in the direct striatal pathway. Here, DRD1 is linked to Hyperammonemia.