Relation of renal cortical gluconeogenesis, glutamate content, and production of ammonia
Related Experiment Videos
Contact us if these videos are not relevant.
Contact us if these videos are not relevant.
View abstract on PubMed
Summary
This summary is machine-generated.Renal ammonia production is not solely determined by glutamate levels. Increased gluconeogenesis may support, but not initiate, higher ammonia production in acidosis and potassium depletion.
Area Of Science
- Biochemistry
- Renal Physiology
- Metabolic Regulation
Background
- Glutamate normally inhibits phosphate-dependent glutaminase (PDG).
- Renal cortical glutamate decreases in metabolic acidosis, potentially activating PDG and increasing ammonia production.
- This glutamate decrease was attributed to increased conversion of glutamate to glucose (gluconeogenesis).
Purpose Of The Study
- To investigate the role of cortical glutamate concentration and gluconeogenesis in regulating renal ammonia production.
- To determine if glutamate levels are the primary driver of increased ammoniagenesis in metabolic acidosis and potassium depletion.
Main Methods
- Administration of ammonium chloride to rats.
- Analysis of kidney cortex from potassium-depleted rats.
- In vitro incubation of rat cortical slices at varying pH levels.
- Measurement of ammonia production, PDG activity, glutamate content, and glutamate-to-glucose conversion rates.
Main Results
- Ammonium chloride administration increased ammonia production and PDG activity without decreasing glutamate.
- Potassium depletion increased ammonia production and PDG activity, but glutamate levels remained normal.
- Cortical glutamate levels did not correlate with ammonia production across different pH conditions.
- Increased gluconeogenesis in potassium-depleted rats did not alter glutamate content.
- In vitro, calcium enhanced glutamate-to-glucose conversion without affecting glutamate levels, while theophylline suppressed gluconeogenesis and decreased glutamate.
Conclusions
- Cortical glutamate concentration is not the major determinant of renal ammonia production.
- Increased cortical gluconeogenesis in acidosis and potassium depletion is unlikely the primary cause of increased ammonia production.
- Enhanced gluconeogenesis may contribute to sustained ammoniagenesis by facilitating the removal of glutamine degradation products.
Related Experiment Videos
Contact us if these videos are not relevant.
Contact us if these videos are not relevant.