Na+,K(+)-ATPase activities are increased in brain in both congenital and acquired hyperammonemic syndromes.

Abstract Activities of Na + ,K + -ATPase were measured in brain regions of experimental animals with either congenital or acquired hyperammonemic. In the sparse-fur (spf) mutant mouse, with a genetic X-linked deficiency of ornithine transcarbamylase, an animal model of congenital hyperammonemia, Na + ,K + -ATPase was increased in frontal cortex (by 57%, P P P P + ,K + -ATPase activities were increased in cerebellum and striatum (by 19%, P P + ,K + -ATPase and the subsequent alteration of neuronal excitability could contribute to the CNS dysfunction characteristic of chronic hyperammonemic syndromes.