Hepatic Denervation Alters the Disposition of an Enteral Glucose Load in Conscious Dogs

Abstract

The aim of this study was to establish the role of nerves to the liver in the disposal of an enteral glucose load. Dogs underwent a laparotomy during which the nerves to the liver were either left intact (C; n = 10) or removed (DN; n = 10). Absence of measurable liver norepinephrine was used to indicate completeness of denervation. Four weeks following surgery, 18-h fasted conscious dogs were given a glucose load (0.7 g/kg body weight) by gavage, and arterial blood samples were drawn over a 180-min period. The glucose and insulin excursions from baseline (incremental area) were 29% and 22% greater (P greater than 0.05) in DN than in C, respectively. Resting blood lactate levels were similar between groups, but they increased significantly more (P less than 0.05) following the administration of the glucose load in DN (peak change from resting level was 376 +/- 90 mumol/L in C and 728 +/- 81 mumol/L in DN). No significant differences between groups in glucagon, glycerol or alanine concentration were evident either prior to or following glucose administration. These data demonstrate that hepatic nerves can influence the substrate and hormone environment following an enteral glucose load.