Diabetes, Vol 49, Issue 3 450-456, Copyright © 2000 by American Diabetes Association
Renal glucose production compensates for the liver during the anhepatic phase of liver transplantation
SE Joseph, N Heaton, D Potter, A Pernet, MA Umpleby and SA Amiel
Department of Medicine and Surgery, Guy's, King's and St Thomas' School of Medicine, London, UK. stonnyj@hotmail.com
The extent of the renal contribution to postabsorptive endogenous glucose
production (EGP) in humans is controversial. We measured EGP in the absence
of the liver during the anhepatic phase (AH) of liver transplantation in
five patients (aged 46.4+/-10.2 years, two women). Stable labeling of
plasma glucose (PG) was achieved for a 2-h period before the AH by primed
continuous infusion of di-deuterated 6,6[2H2]glucose (1.7 mg/min) and
continued throughout the AH. PG was maintained above the fasting level
(6.1+/-2.73 mmol/l) with 5% dextrose labeled with 6,6[2H2]glucose
throughout the AH (mean level during the AH 0.98+/-0.45 mg x kg(-1) x
min(-1)). Isotopic enrichment remained stable at 0.84+/-0.21% atom percent
excess throughout. EGP, calculated by use of a modified Steele equation,
decreased from 2.6+/-1.24 at baseline to 0.97+/-0.9 mg x kg(-1) x min(-1)
(36% baseline, P = 0.045) but recovered at approximately 30 min to reach
1.38+/-0.83 mg x kg(-1) x min(-1) (54% baseline) by 60 min. Epinephrine,
lactate, free fatty acid, and glycerol levels increased significantly
(0.79+/-0.74 to 3.65+/-2.1 nmol/l, P = 0.005; 1.88+/-0.43 to 3.46+/-0.9
mmol/l, P = 0.024; 543.9+/-215.5 to 705.5+/-219.2 micromol/l, P = 0.012;
75.6+/-30.2 to 139+/-96.3 micromol/l, P = 0.003, respectively). These data
show that postabsorptive nonhepatic glucose production in humans may
contribute to greater than one-third of overall EGP, increasing when
required, and that it is associated with a stress response and increased
gluconeogenic substrate availability. We conclude that extrahepatic
tissues, most notably those of the kidney, make a significant contribution
to EGP in humans.