"NBCe1-A deletion caused severe spontaneous metabolic acidosis in mice and partly blocked increased NH4 excretion after exogenous acid loading. Deletion altered the expression of multiple enzymes involved in proximal tubule ammonia generation but not proteins involved in collecting duct ammonia secretion. NBCe1-A has a critical role in basal and acidosis-stimulated NH4 metabolism by regulating proximal tubule NH4 enzymes."xsd:string