Ca/sup 2 +/ and glucose uptake in adipocytes: evidence for biological activity of a Ca/sup 2 +/-palmitate complex

Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:7171306

Thode, J; Pershadsingh, H A; Shade, D L; McDonald, J M; Ladenson, J H

A tightly bound form of Ca/sup 2 +/ in serum, thought to be a Ca/sup 2 +/-fatty acid complex, has been reported to cause accelerated Ca/sup 2 +/ uptake in bone cells. The authors therefore studied the effect of palmitic acid on Ca/sup 2 +/ accumulation and its influence on glucose transport in adipocytes. They assessed /sup 45/Ca/sup 2 +/ and /sup 14/C-D-glucose uptake into rat adipocytes from solutions containing: 4% (w/v) fatty acid-free albumin, 2.5 mM CaCl/sub 2/ (free (Ca/sup 2 +/)=1.30 mM), 140 mM NaCl, 3 mM Na phosphate, 1.4 mM MgSO/sub 4/, 5 mM D-glucose, 5 mM HEPES, pH 7.4 at 37/sup 0/C with and without 4 mM palmitate. Ca/sup 2 +/ was taken up by both rapid (< 30 sec), and slow (reaching steady state within 20 min) cellular accumulation phases. Palmitate increased the rapid binding phase of /sup 45/Ca/sup 2 +/ uptake from 2.10 +/- 0.13 to 3.03 +/- 0.16 fmol Ca/sup 2 +//cell and caused a 2 to 3-fold increase in the slow phase. Palmitate also increased glucose uptake by a mean of 225% above control. This increase was eliminated by a 15 min preincubation with the intracellular Ca/sup 2 +/ chelator, quin 2-AM (50 ..mu..M), implying that increased Ca/sup 2 +/ uptake was related to increased glucose transport. They conclude that the Ca/sup 2 +/-palmitate complex enhances Ca/sup 2 +/ uptake, which may be related to an increased ability for adipocytes to transport glucose. The Ca/sup 2 +/-palmitate complex may therefore represent a biologically active form of Ca/sup 2 +/.

• Research Organization: Washington Univ. School of Medicine, St. Louis, MO
• OSTI ID: 7171306
• Report Number(s): CONF-8606151-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:6; ISSN FEPRA
• Country of Publication: United States
• Language: English

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59 BASIC BIOLOGICAL SCIENCES
ALBUMINS
ALDEHYDES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL ACCUMULATION
BIOLOGICAL EFFECTS
CALCIUM 45
CALCIUM COMPOUNDS
CALCIUM ISOTOPES
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CATIONS
CHARGED PARTICLES
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
EVEN-ODD NUCLEI
FAT CELLS
GLUCOSE
HEXADECANOIC ACID
HEXOSES
INTERMEDIATE MASS NUCLEI
IONS
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
MAMMALS
MEMBRANE TRANSPORT
MONOCARBOXYLIC ACIDS
MONOSACCHARIDES
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PROTEINS
RADIOISOTOPES
RATS
RODENTS
SACCHARIDES
SOMATIC CELLS
TRACER TECHNIQUES
UPTAKE
VERTEBRATES