Open AccessThe Regulation of Glyceride Synthesis from Pyruvate in Isolated Fat Cells
Author(s) -
Saggerson E. David,
Tomassi G.
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb01597.x
Subject(s) - glyceride , phosphoenolpyruvate carboxykinase , glycerol , pyruvate carboxylase , fatty acid synthesis , biochemistry , carbohydrate , lipogenesis , fatty acid , adipose tissue , enzyme , chemistry , biology , pyruvic acid , palmitic acid , medicine , endocrinology
The incorporation of 14 C‐labelled pyruvate into glyceride fatty acids and glyceride glycerol has been measured in fat cells prepared from epididymal adipose tissues of normal rats, rats starved for 24 h, rats starved for 24 h and refed a carbohydrate diet for 24 h or rats starved for 24 h and refed a fat diet for 24 h. Rates of fatty acid synthesis were decreased in starved and starved, fat refed cells and increased in starved, carbohydrate refed cells. In all four dietary states, addition of palmitate to the incubation medium resulted in increased rates of glyceride glycerol formation and decreased rates of fatty acid synthesis from 14 C‐labelled pyruvate. In normal cells these effects of palmitate were maximal below 1 mM palmitate. Dietary‐induced alterations in incorporation of 14 C‐labelled pyruvate into glyceride glycerol, maximised by addition of palmitate, correlated well with corresponding alterations in the activity of extramitochondrial phosphoenolpyruvate carboxykinase in the cells, but did not correlate with alterations in the activity of pyruvate carboxylase or mitochondrial phosphoenolpyruvate carboxykinase. Use of marker enzymes allowed an assessment to be made of the distribution of these enzymes between extramitochondrial and mitochondrial spaces.