Effect of fast duration on disposition of an intraduodenal glucose load in the conscious dog.

Galassetti P, Hamilton KS, Gibbons FK, Bracy DP, Lacy DB, Cherrington AD, Wasserman DH
Am J Physiol. 1999 276 (3): E543-52

PMID: 10070022 · DOI:10.1152/ajpendo.1999.276.3.E543

UNLABELLED - The effects of prior fast duration (18 h, n = 8; 42 h, n = 8) on the glycemic and tissue-specific responses to an intraduodenal glucose load were studied in chronically catheterized conscious dogs. [3-3H]glucose was infused throughout the study. After basal measurements, glucose spiked with [U-14C]glucose was infused for 150 min intraduodenally. Arterial insulin and glucagon were similar in the two groups. Arterial glucose (mg/dl) rose approximately 70% more during glucose infusion after 42 h than after an 18-h fast. The net hepatic glucose balance (mg. kg-1. min-1) was similar in the two groups (basal: 1.8 +/- 0.2 and 2.0 +/- 0.3; glucose infusion: -2.2 +/- 0.5 and -2.2 +/- 0.7). The intrahepatic fate of glucose was 79% glycogen, 13% oxidized, and 8% lactate release after a 42-h fast; it was 23% glycogen, 21% oxidized, and 56% lactate release after an 18-h fast. Net hindlimb glucose uptake was similar between groups. The appearance of intraduodenal glucose during glucose infusion (mg/kg) was 900 +/- 50 and 1,120 +/- 40 after 18- and 42-h fasts (P < 0.01).

CONCLUSION - glucose administration after prolonged fasting induces higher circulating glucose than a shorter fast (increased appearance of intraduodenal glucose); liver and hindlimb glucose uptakes and the hormonal response, however, are unchanged; finally, an intrahepatic redistribution of carbons favors glycogen deposition.

MeSH Terms (19)

Alanine Animals Blood Glucose Dogs Duodenum Fasting Fatty Acids, Nonesterified Female Glucose Glycerol Glycogen Hindlimb Intestinal Mucosa Lactic Acid Liver Male Muscle, Skeletal Pancreatic Hormones Time Factors

Connections (2)

This publication is referenced by other Labnodes entities: