Influence of extracellular HCO/sub 3//sup -/ and pH on lysine (LYS) and leucine (LEU) uptake and metabolism in swine renal tubules

Conference · Sat Mar 01 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5320770

Patience, J F; Esteve-Garcia, E; Austic, R E

Fragments of renal tubules prepared by collagenase treatment of renal cortex were suspended to Krebs-Henseleit buffers which were modified to contain 10, 25 and 35 mM HCO/sub 3//sup -/ at pH 7.4, or 25 mM HCO/sub 3//sup -/ at pH 7.1, 7.4 and 7.7. Buffers were oxygenated with O/sub 2/-CO/sub 2/ gas mixtures varying in carbon dioxide concentration prior to incubation. Approximately 100 mg tubules were incubated with shaking at 37/sup 0/C for 30 min in serum-stoppered 25 ml Erlenmeyer flasks in 3.0 ml of buffer containing 0.1% dialyzed bovine serum albumin, 5 mM D-glucose and 0.3 mM L-(U-/sup 14/C)-lysine or L-(1-/sup 14/C)-leucine. The incorporation of carbon-14 into CO/sub 2/ and into 10% sulfosalicylic acid (SSA)-soluble and SSA-insoluble fractions of the incubation mixture was determined. Low (10mM) bicarbonate reduced the incorporation of lys and leu into protein but did not substantially affect the recovery of /sup 14/CO/sub 2/ from either amino acid. High pH (7.7) resulted in reduced incorporation of lys and leu into protein, and decreased the oxidation of lys but not leu. The specific activity of lys (leu was not determined) in the SSA-soluble fraction was unaffected by bicarbonate or pH. The authors conclude that variations in extracellular pH and HCO/sub 3//sup -/ (or pCO/sub 2/) affect the metabolism of amino acids by renal tubules and that low extracellular HCO/sub 3//sup -/ (or pCO/sub 2/) may depress the incorporation of amino acids into protein.

• Research Organization: Cornell Univ., Ithaca, NY
• OSTI ID: 5320770
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:3
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID CARBONATES
AMINO ACIDS
BIOLOGICAL EFFECTS
BODY
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBOXYLIC ACIDS
CHALCOGENIDES
ISOTOPE APPLICATIONS
KIDNEYS
LABELLED COMPOUNDS
LEUCINE
LYSINE
METABOLISM
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
OXIDES
OXYGEN COMPOUNDS
PH VALUE
TRACER TECHNIQUES
TUBULES
UPTAKE