Degradation of glucose-metabolizing enzymes in the rat small intestine during starvation.
1. The degradation rates and half-lives of hexokinase, 6-phosphogluconate dehydrogenase, lactate dehydrogenase, pyruvate kinase, glucose 6-phosphate dehydrogenase, phosphoglycerate kinase and aldolase were calculated from measurements of the decline in activities of these enzymes in rat small intestine during starvation. 2. The half-lives of the enzymes are: hexokinase, 5.7h; 6-phosphogluconate dehydrogenase, 7.6h; glucose 6-phosphate dehydrogenase, 6.0h; pyruvate kinase, 8.9h; lactate dehydrogenase, 8.7h; phosphoglycerate kinase, 8.7h; aldolase, 5.1h. 3. The significance of the results is discussed with respect to the regulation of enzyme concentrations in response to changes in diet.
D000818:Animals; D001345:Autoradiography; D005634:Fructose-Bisphosphate Aldolase / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D006207:Half-Life; D006593:Hexokinase / Q000378:metabolism; D007421:Intestine, Small / Q000166:cytology / Q000201:enzymology*; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D008433:Mathematics; D010734:Phosphogluconate Dehydrogenase / Q000378:metabolism; D010735:Phosphoglycerate Kinase / Q000378:metabolism; D011770:Pyruvate Kinase / Q000378:metabolism; D051381:Rats; D013056:Spectrophotometry, Ultraviolet; D013217:Starvation; D013997:Time Factors; D014316:Tritium
D014316:Tritium; D007770:L-Lactate Dehydrogenase; D010734:Phosphogluconate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D006593:Hexokinase; D011770:Pyruvate Kinase; D010735:Phosphoglycerate Kinase; D005634:Fructose-Bisphosphate Aldolase; D005947:Glucose