Carbamyl phosphate and glutamine stimulation of the gallbladder salt pump
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Carbamyl phosphate stimulates neutral salt transport in thein vitro gallbladder. Acetyl phosphate also stimulates transport. In addition, the metabolic precursors of carbamyl phosphate, glutamine and bicarbonate ion, stimulate transport of fluid across the gallbladder mucosa. These data suggest that the effect of glutamine in stimulating increases in transport is achieved via the synthesis of carbamyl phosphate which in turn reacts with the transport mechanism. Metabolic precursors of glutamine, glutamate plus a nitrogen source, when combined will produce an effect similar to glutamine alone. Fluid transport is also slowed by azaserine; thus, the stimulation effect appears to be restricted to glutamine.
KeywordsNitrogen Phosphate Glutamate Bicarbonate Glutamine
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