Intraportal glucose delivery significantly increased net hepatic glucose uptake by two- to threefold compared to peripheral glucose delivery alone across a physiological range of insulin levels.
Does intraportal glucose delivery alter the relationship between net hepatic glucose uptake and insulin concentration in fasted dogs?
Intraportal glucose delivery significantly enhances net hepatic glucose uptake compared to peripheral delivery alone across a physiological range of insulin levels, indicating the 'portal signal' is a critical determinant of hepatic glucose disposal.
Absolute Event Rate: 5.52% vs 3.04%
p-value: p=<0.05
To examine the relationship between net hepatic glucose uptake (NHGU) and the insulin level and to determine the effects of portal glucose delivery on that relationship, NHGU was evaluated at three different insulin levels in seven 42-h-fasted, conscious dogs during peripheral glucose delivery and during a combination of peripheral and portal glucose delivery. During peripheral glucose delivery, at arterial blood glucose levels of approximately 175 mg/dl and insulin levels reaching the liver of 51 +/- 2, 92 +/- 6, and 191 +/- 6 microU/ml, respectively, NHGUs were 0.55 +/- 0.30, 1.52 +/- 0.44, and 3.04 +/- 0.79 mg/kg per min, respectively. At hepatic glucose loads comparable to those achieved during peripheral glucose delivery and inflowing insulin levels of 50 +/- 4, 96 +/- 5, and 170 +/- 8 microU per ml, respectively, NHGUs were 1.96 +/- 0.48, 3.67 +/- 0.68, and 5.52 +/- 0.92 mg/kg per min when a portion of the glucose load was delivered directly into the portal vein. The results of these studies thus indicate that net hepatic glucose uptake is dependent on both the plasma insulin level and the route of glucose delivery and that under physiological conditions the "portal" signal is at least as important as insulin in the determination of net hepatic glucose uptake.
Myers et al. (Fri,) conducted a other in Healthy (fasted) (n=7). Intraportal glucose delivery vs. Peripheral glucose delivery alone was evaluated on Net hepatic glucose uptake (NHGU) at highest insulin level (p=<0.05). Intraportal glucose delivery significantly increased net hepatic glucose uptake by two- to threefold compared to peripheral glucose delivery alone across a physiological range of insulin levels.