TABLE 1

Hepatic glucose flux, plasma hormones, enzyme activities, and metabolites in 20-week-old ZCL and AdvCMV-GKL–treated ZDF rats, as measured before (basal) and during (clamp) a hyperglycemic clamp

BasalClamp
ZCLZDF-LZDF-NZDF-HZCLZDF-LZDF-NZDF-H
n58775877
Body weight (g)407 ± 16366 ± 8*376 ± 6*372 ± 5*
Plasma
Glucose (mmol/l)7.4 ± 0.323.9 ± 1.2*13.6 ± 0.9*9.5 ± 0.4*24.7 ± 0.927.4 ± 1.425.5 ± 2.028.0 ± 1.8
Insulin (pmol/l)291 ± 30341 ± 20324 ± 31337 ± 40360 ± 15354 ± 27365 ± 38353 ± 59
Glucagon (ng/l)48 ± 344 ± 145 ± 348 ± 444 ± 240 ± 340 ± 346 ± 5
FFAs (mmol/l)0.78 ± 0.161.08 ± 0.241.05 ± 0.270.99 ± 0.300.70 ± 0.191.43 ± 0.24*1.54 ± 0.27*1.68 ± 0.28*
Triglyceride (mg/ml)0.35 ± 0.114.44 ± 0.18*5.00 ± 0.62*6.22 ± 0.76*0.52 ± 0.145.24 ± 1.38*5.73 ± 1.00*7.25 ± 1.13*
Blood
Lactate (mmol/l)0.59 ± 0.091.92 ± 0.21*2.39 ± 0.26*2.51 ± 0.21*1.54 ± 0.29‡2.16 ± 0.20*3.96 ± 0.58*†‡4.80 ± 0.48*†‡
Alanine (mmol/l)1.91 ± 0.171.47 ± 0.15*1.55 ± 0.10*1.48 ± 0.12*1.90 ± 0.451.24 ± 0.13*1.70 ± 0.171.46 ± 0.15
Rate
    Glucose turnover (μmol · kg−1 · min−1)38 ± 380 ± 3*56 ± 2*†63 ± 4*†94 ± 6‡98 ± 7100 ± 8‡132 ± 8*†‡
    Glucose infusion (μmol · kg−1 · min−1)0000111 ± 822 ± 10*88 ± 11†143 ± 6*†
    Glucose cycling (μmol · kg−1 · min−1)18 ± 761 ± 5*56 ± 6*75 ± 9*53 ± 1562 ± 5*82 ± 9*90 ± 7*
    Glucose production (μmol · kg−1 · min−1)38 ± 380 ± 3*56 ± 2*†63 ± 4*†−7 ± 4‡80 ± 7*13 ± 11†‡−9 ± 7†‡
    G-6-Pase flux (μmol · kg−1 · min−1)58 ± 8150 ± 11*110 ± 8*†133 ± 11*45 ± 6142 ± 7*95 ± 13*†81 ± 10*†‡
Glucokinase activity
    Average (mU/mg protein)32.5 ± 3.211.6 ± 1.9*34.5 ± 4.2†77.8 ± 4.6*†
    Range (mU/mg protein)28–404–1821–5563–91
G-6-Pase
    Activity (mU/mg protein)777 ± 68858 ± 53805 ± 72763 ± 59
    Km for G-6-P (mmol/l)2.49 ± 0.042.52 ± 0.042.51 ± 0.062.50 ± 0.05
Glycogen phosphorylase a (units/g liver)16.1 ± 1.423.3 ± 2.7*20.1 ± 4.219.1 ± 3.1
Glycogen synthase
    Total (units/g liver)0.98 ± 0.040.89 ± 0.030.95 ± 0.010.88 ± 0.04
    Active form (units/g liver)0.12 ± 0.030.06 ± 0.01*0.11 ± 0.03†0.13 ± 0.02†
    % Active12.3 ± 3.76.6 ± 0.9*11.5 ± 2.614.5 ± 1.6
Content
    G-6-P (nmol/g liver)203 ± 39118 ± 8*242 ± 23†395 ± 42*†
    Glycogen (μmol glucose/g liver)184 ± 33249 ± 27381 ± 63*†475 ± 52*†
    Glycogen–new synthesis (μmol glucose/g liver)43 ± 315 ± 5*47 ± 7†68 ± 6*†
  • ZDF rats were divided into three groups based on the level of hepatic GK activity achieved by AdvCMV-GKL treatment relative to ZCL rats (ZDF-L, <ZCL; ZDL-N, =ZCL; ZDF-H, >ZCL). Significant differences (P < 0.05) from the corresponding values of the

  • * ZCL group, from the

  • ZDF-L group, and from

  • basal values within the same group are indicated.