Hepatic metabolism of anaesthetized growing pigs during acute portal infusion of volatile fatty acids and hydroxy-methyl butyrate

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review


ABSTRACT: The objective of the experiment was to study hepatic metabolism during infusion of volatile fatty acids (VFA) differing in amounts and composition or infusion of HMB. Three fasted (20 h) pigs (mean BW ± SE; 58 kg ± 1) were fitted with indwelling catheters in the portal vein, hepatic vein, mesenteric artery and two in mesenteric veins. One of the mesenteric vein catheters was used to infuse VFA in the anesthetized pigs to mimic effects of increased consumption of dietary fibers. Sixteen sets of blood samples were simultaneously drawn from the artery and portal and hepatic veins at 15 min intervals and analyzed for contents of paraamino- hippuric acid (PAH; blood flow marker) and plasma metabolites. Total VFA was infused at a rate of 0 mmol/h (background; Inf1, Inf6), 60 mmol/h (Inf2) or 120 mmol/h (Inf3 to Inf5). Infused VFA contained 70, 20, and 5% of acetate, propionate, and butyrate, respectively, for Inf2 and Inf3, or 65%, 20%, and 10% of acetate, propionate, and butyrate, respectively, for Inf4 and Inf5. In addition, for Inf5, HMB was infused at 2 mmol/h. Statistical analysis included fixed effects of infusion and interaction between infusion and samplings within infusion while accounting for repeated measurements. A net hepatic uptake of propionate, butyrate, and lactate was observed, whereas the liver released acetate, glucose, and urea. The portal lactate absorption could not account for the net hepatic uptake of lactate, suggesting lactate originated from partial oxidation of glycogen in peripheral muscle tissues. The net hepatic lactate uptake could account for 29% to 84% of the hepatic glucose released during VFA infusions. Net portal recovery rates of infused VFA were between 90% and 105%, indicating that PAH is a reliable blood flow marker. In conclusion, lactate and AA from peripheral tissues were likely the two most important glycogenic precursors for gluconeogenesis in the liver during fasting.
Original languageEnglish
JournalJournal of Animal Science
IssueSuppl. 3
Pages (from-to)324-327
Number of pages4
Publication statusPublished - 9 Nov 2016

    Research areas

  • dietary fiber, fermentation, liver, plasma flow, quantitative metabolism

See relations at Aarhus University Citationformats

ID: 104986530