TABLE 2

Effect of leptin infusion on the indirect pathway of hepatic UDP-glucose formation

[14C]PEP (dpm/nmol)[14C]UDP-glucose (dpm/nmol)Indirect pathway (%)
3-Day control
 Vehicle12.2 ± 2.511.8 ± 1.548 ± 5
 Leptin13.2 ± 1.921.8 ± 3.183 ± 5*
3-Day pair-fed
 Vehicle14.3 ± 3.111.9 ± 1.843 ± 9
 Leptin11.9 ± 2.021.0 ± 3.687 ± 6*
3-Day ad libitum
 Vehicle11.4 ± 1.811.3 ± 1.249 ± 10
 Leptin14.1 ± 4.210.4 ± 3.443 ± 9
7-Day control
 Vehicle14.0 ± 2.111.9 ± 1.844 ± 6
 Leptin15.1 ± 2.523.8 ± 3.179 ± 4*
7-Day pair-fed
 Vehicle19.7 ± 2.518.8 ± 1.144 ± 5
 Leptin20.3 ± 2.235.6 ± 4.989 ± 7*
7-Day ad libitum
 Vehicle10.9 ± 1.410.4 ± 0.748 ± 5
 Leptin14.6 ± 2.111.8 ± 2.439 ± 6
  • Data are means ± SE. Specific activities of UDP-glucose and PEP were used to calculate the contribution of PEP-gluconeogenesis (indirect pathway) to the hepatic UDP-glucose pool after [U-14C]lactate infusion in rats during vehicle or leptin administration. The indirect pathway is the percent of the hepatic UDP-glucose pool derived from PEP-gluconeogenesis, calculated as the ratio of the specific activities of [14C]UDP-glucose and 2 × [14C]PEP.

  • *

    * P < 0.01 vs. vehicle.