TY - JOUR
T1 - Effects of Hepatic Glycogen Content on Hepatic Insulin Action in Humans
T2 - Alteration in the Relative Contributions of Glycogenolysis and Gluconeogenesis to Endogenous Glucose Production
AU - Wise, Steven
AU - Nielsen, Michael
AU - Rizza, Robert
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1997
Y1 - 1997
N2 - Hepatic glycogen content varies by almost 2-fold during the day, generally increasing from a nadir before breakfast to a peak 4-5 h after supper. To determine whether differences in hepatic glycogen content of this magnitude alter hepatic insulin action, nine subjects were studied on two occasions. On one occasion saline was infused, whereas on the other occasion an infusion of glucose [16.4 μmol/kg lean body mass (-Ibm)·min] was started immediately after supper and continued throughout the night so as to spare hepatic glycogen. The nocturnal glucose infusion resulted in higher (P < 0.05) plasma glucose (6.0 ± 0.1 vs. 5.1 ± 0.1 mmol/L) and insulin (127 ± 38 vs. 49 ± 9 pmol/L) concentrations, and lower (P < 0.05) plasma glucagon concentrations (74 ± 11 vs. 97 ± 20 pg/mL) than did saline infusion. As anticipated, endogenous glucose production (EGP) was substantially lower (P < 0.001) during the glucose than during the saline infusion (7.0 ± 0.9 vs. 19.4 + 1.3 μmol/kg-lbm·min). After discontinuation of the glucose infusion, glucose and insulin concentrations fell to levels that no longer differed from those observed during the saline infusion. In contrast, EGP increased to rates that were higher (P < 0.05) than those observed over the same interval after overnight saline infusion (19.2 ± 1.2 vs. 16.5 ± 0.7 μmol/kg-lbm·min). Despite higher EGP, the rate of incorporation of 14CO2 into glucose was lower (P < 0.001) after glucose than that after saline infusion (9.8 ± 1.2% vs. 24.4 ± 3.0%), implying a reciprocal relationship between hepatic glycogen content and gluconeogenesis. On the other hand, when differences in basal rates were taken into account, insulin-induced suppression of both EGP and incorporation of 14CO2 into glucose did not differ on the two occasions. Thus, whereas hepatic glycogen content influences both the absolute rate of EGP and the percent contribution of gluconeogenesis to EGP, it does not alter hepatic insulin action.
AB - Hepatic glycogen content varies by almost 2-fold during the day, generally increasing from a nadir before breakfast to a peak 4-5 h after supper. To determine whether differences in hepatic glycogen content of this magnitude alter hepatic insulin action, nine subjects were studied on two occasions. On one occasion saline was infused, whereas on the other occasion an infusion of glucose [16.4 μmol/kg lean body mass (-Ibm)·min] was started immediately after supper and continued throughout the night so as to spare hepatic glycogen. The nocturnal glucose infusion resulted in higher (P < 0.05) plasma glucose (6.0 ± 0.1 vs. 5.1 ± 0.1 mmol/L) and insulin (127 ± 38 vs. 49 ± 9 pmol/L) concentrations, and lower (P < 0.05) plasma glucagon concentrations (74 ± 11 vs. 97 ± 20 pg/mL) than did saline infusion. As anticipated, endogenous glucose production (EGP) was substantially lower (P < 0.001) during the glucose than during the saline infusion (7.0 ± 0.9 vs. 19.4 + 1.3 μmol/kg-lbm·min). After discontinuation of the glucose infusion, glucose and insulin concentrations fell to levels that no longer differed from those observed during the saline infusion. In contrast, EGP increased to rates that were higher (P < 0.05) than those observed over the same interval after overnight saline infusion (19.2 ± 1.2 vs. 16.5 ± 0.7 μmol/kg-lbm·min). Despite higher EGP, the rate of incorporation of 14CO2 into glucose was lower (P < 0.001) after glucose than that after saline infusion (9.8 ± 1.2% vs. 24.4 ± 3.0%), implying a reciprocal relationship between hepatic glycogen content and gluconeogenesis. On the other hand, when differences in basal rates were taken into account, insulin-induced suppression of both EGP and incorporation of 14CO2 into glucose did not differ on the two occasions. Thus, whereas hepatic glycogen content influences both the absolute rate of EGP and the percent contribution of gluconeogenesis to EGP, it does not alter hepatic insulin action.
UR - http://www.scopus.com/inward/record.url?scp=0031154906&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031154906&partnerID=8YFLogxK
U2 - 10.1210/jc.82.6.1828
DO - 10.1210/jc.82.6.1828
M3 - Article
C2 - 9177391
AN - SCOPUS:0031154906
SN - 0021-972X
VL - 82
SP - 1828
EP - 1833
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 6
ER -