Estimation of pyruvate recycling during gluconeogenesis in perfused rat liver
MetabolismPublished 1 January 1971
Bernice Friedman, EDWARD H. GOODMAN, Harry L. Saunders, Vincent Kostos, Sidney Weinhouse
Citations53
SJR quartileQ1
SJR score3.53
SNIP2.32
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TL;DR
The results suggest a marked inhibition of pyruvate kinase in fasted rat liver as a probable factor in the conversion of pyRuvate to glucose.
Abstract
An isotope tracer procedure is described for determination of pyruvate "recycling" during gluconeogenesis from pyruvate, and results are given of its application to a study of gluconeogenesis from pyruvate-2-14C in perfused rat liver. After one hour perfusion at 37° C, lactate, pyruvate, and glucose were isolated and radioactivity determined in each carbon atom. Recycling is estimated from the extent of incorporation of 14C in carbons 1 and 3 of the 3-carbon acids. In livers from fasted rats approximately twice as much pyruvate was converted to glucose as was recycled, whereas in livers from fed rats only about one fourth as much was converted to glucose as was recycled. This pattern was not altered significantly with the simultaneous presence and oxidation of octanoate in the perfused livers. The results suggest a marked inhibition of pyruvate kinase in fasted rat liver as a probable factor in the conversion of pyruvate to glucose.
Keywords
Biochemistry, Genetics and Molecular Biology
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