Renal hydroxybutyrate and acetoacetate reabsorption and utilization in the rat. 1985

M Barac-Nieto

Is the renal conservation of ketones effected through saturable transport systems? Does the renal reabsorption of ketoacids limit their utilization? The reabsorptive transport (T) and metabolic utilization (Q) of D-3-hydroxybutyrate (HB) and acetoacetate (AA) in the kidney were measured in anesthetized rats by use of clearance and arteriovenous extraction determinations. THB and TAA increased in proportion with increasing HB and AA filtered loads. Fractional THB decreases from 0.97 to 0.72 upon increases in the plasma HB. Fractional TAA also decreases from 0.89 to 0.73, at a constant filtered AA load, when the filtered HB load increased. Thus both saturable and nonsaturable components effect the reabsorption of HB and AA. Renal QHB increased from 0.4 to 4 mumol X g-1 X min-1 on increase in the plasma HB. THB always exceeded the simultaneously measured QHB. However, QHB was significantly correlated with THB, suggesting that QHB may be limited by delivery of HB to the renal cells through reabsorptive pathways. There was no net renal conversion of HB and AA. Both HB and AA were utilized by the kidney. Thus, utilized ketoacids must have entered pathways for complete oxidation or for synthesis (lipid?) in the kidney.

UI MeSH Term Description Entries
D007662 Ketosis A condition characterized by an abnormally elevated concentration of KETONE BODIES in the blood (acetonemia) or urine (acetonuria). It is a sign of DIABETES COMPLICATION, starvation, alcoholism or a mitochondrial metabolic disturbance (e.g., MAPLE SYRUP URINE DISEASE). Ketoacidosis,Metabolic Ketoacidosis,Metabolic Ketosis,Acetonemia,Acetonuria,Ketoacidemia,Ketoaciduria,Ketonemia,Ketonuria,Acetonemias,Acetonurias,Ketoacidemias,Ketoacidoses,Ketoacidoses, Metabolic,Ketoacidosis, Metabolic,Ketoacidurias,Ketonemias,Ketonurias,Ketoses, Metabolic,Ketosis, Metabolic,Metabolic Ketoacidoses,Metabolic Ketoses
D007668 Kidney Body organ that filters blood for the secretion of URINE and that regulates ion concentrations. Kidneys
D008297 Male Males
D010084 Oxidation-Reduction A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471). Redox,Oxidation Reduction
D002250 Carbon Radioisotopes Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes. Radioisotopes, Carbon
D005919 Glomerular Filtration Rate The volume of water filtered out of plasma through glomerular capillary walls into Bowman's capsules per unit of time. It is considered to be equivalent to INULIN clearance. Filtration Rate, Glomerular,Filtration Rates, Glomerular,Glomerular Filtration Rates,Rate, Glomerular Filtration,Rates, Glomerular Filtration
D006885 Hydroxybutyrates Salts and esters of hydroxybutyric acid. Hydroxybutyric Acid Derivatives,Hydroxybutyric Acids,Acid Derivatives, Hydroxybutyric
D000090 Acetoacetates Salts and derivatives of acetoacetic acid.
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D001692 Biological Transport The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments. Transport, Biological,Biologic Transport,Transport, Biologic

Related Publications

M Barac-Nieto
February 1954, The American journal of physiology,
M Barac-Nieto
April 1969, Clinica chimica acta; international journal of clinical chemistry,
M Barac-Nieto
November 1997, American journal of clinical pathology,
M Barac-Nieto
May 1968, Biochemical and biophysical research communications,
M Barac-Nieto
January 1988, Ukrainskii biokhimicheskii zhurnal (1978),
Copied contents to your clipboard!