Biomaterial Database

Effects of cell density on in vitro glucose metabolism by isolated adipocytes. 1993

M Digirolamo, and S V Thacker, and S K Fried

Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30329.

We studied the effect of variable isolated fat cell concentrations (from 0.17 to 1.25 x 10(6) cells/ml) on rate and pattern of basal and insulin-stimulated glucose metabolism by rat epididymal fat cells. Cell concentration did not affect total glucose utilization, but high cell concentrations increased the absolute and relative conversion of glucose to CO2 and glyceride-fatty acids by two- to threefold and decreased the conversion to lactate, pyruvate, and glyceride-glycerol when compared with values observed at low cell concentration. When effects of adenosine deaminase (ADA) and N-6(2-phenylisopropyl)adenosine (PIA) were examined, addition of ADA to incubated cells produced no significant changes in the rate or pattern of adipocyte glucose metabolism; PIA had a slight and uniform effect on the conversion of glucose to its metabolic products and minimal effect on insulin-stimulated glucose metabolism. Medium free fatty acid concentration did not change during the incubation at various cell density, but intracellular free fatty acids were found to be inversely related to fat cell density in the medium. Thus a variable fat cell density influences the pattern of adipocyte glucose metabolism in vitro. This effect may be due to variable rates of lipolysis and resulting changes in intracellular fatty acid concentration rather than to adenosine per se. This work has practical implications in the need to define cell density when carrying out in vitro measurements of adipocyte glucose conversion to products.

UI	MeSH Term	Description	Entries
D007773	Lactates	Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
D008297	Male		Males
D010660	Phenylisopropyladenosine	N-Isopropyl-N-phenyl-adenosine. Antilipemic agent. Synonym: TH 162.	Isopropylphenyladenosine,L-Phenylisopropyladenosine,N(6)-Phenylisopropyl-Adenosine,L Phenylisopropyladenosine
D011773	Pyruvates	Derivatives of PYRUVIC ACID, including its salts and esters.
D002245	Carbon Dioxide	A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.	Carbonic Anhydride,Anhydride, Carbonic,Dioxide, Carbon
D002450	Cell Communication	Any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP.	Cell Interaction,Cell-to-Cell Interaction,Cell Communications,Cell Interactions,Cell to Cell Interaction,Cell-to-Cell Interactions,Communication, Cell,Communications, Cell,Interaction, Cell,Interaction, Cell-to-Cell,Interactions, Cell,Interactions, Cell-to-Cell
D002452	Cell Count	The number of CELLS of a specific kind, usually measured per unit volume or area of sample.	Cell Density,Cell Number,Cell Counts,Cell Densities,Cell Numbers,Count, Cell,Counts, Cell,Densities, Cell,Density, Cell,Number, Cell,Numbers, Cell
D002469	Cell Separation	Techniques for separating distinct populations of cells.	Cell Isolation,Cell Segregation,Isolation, Cell,Cell Isolations,Cell Segregations,Cell Separations,Isolations, Cell,Segregation, Cell,Segregations, Cell,Separation, Cell,Separations, Cell
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D005230	Fatty Acids, Nonesterified	FATTY ACIDS found in the plasma that are complexed with SERUM ALBUMIN for transport. These fatty acids are not in glycerol ester form.	Fatty Acids, Free,Free Fatty Acid,Free Fatty Acids,NEFA,Acid, Free Fatty,Acids, Free Fatty,Acids, Nonesterified Fatty,Fatty Acid, Free,Nonesterified Fatty Acids