The Effect of the Hepatic Nerves on the Disposition of a Mixed Meal by Conscious Dogs

Publisher Website
Google Scholar
Abstract
We examined the disposition of a mixed meal by nine conscious dogs fasted for 24 hours with surgical hepatic denervation. The results were compared with those from identical studies carried out previously in 13 hepatic‐innervated dogs. Net gut release of glucose and gluconeogenic precursors (assessed with the arteriovenous difference technique), the resulting blood glucose and plasma insulin concentrations, and the hepatic glucose load were remarkably similar in the two groups. Net hepatic glucose uptake was 4.8 ± 3.6 g in hepatic‐denervated and 7.7 ± 3.3 g in hepatic‐innervated dogs. Cumulative net hepatic lactate release in hepatic‐denervated dogs was 4.3 ± 1.4 g of glucose equivalents, half the value for hepatic‐innervated dogs. Net hepatic carbon intake was similar in the two groups. Hepatic lipogenesis, oxidation, and net glycogen synthesis were qualitatively similar between groups. In conclusion, the disposition of a mixed meal by hepatic‐innervated and hepatic‐denervated dogs was very similar. Subtle alterations in net hepatic balance of substrates (tendencies toward decreases in net hepatic glucose uptake and lactate release) made net carbon retention in denervated livers virtually identical with that in innervated livers. When other compensatory mechanisms are intact, hepatic denervation does not significantly alter hepatic disposition of a mixed meal. (Journal of Parenteral and Enteral Nutrition 18:248–255, 1994)