Hepatic vagotomy does not alter plasma insulin response to a low dose injection of glucose.
It has been reported that insulin concentration is altered by a hepatic vagotomy following intraperitoneal glucose injection (0.3 g/kg) resulting in supraphysiological blood glucose concentrations. On the other hand, neural activity of the hepatic vagus nerve has been shown to be substantially reduced by lower doses (0.05 g/kg intraportal; 0.1 g/kg intravenous). The present study was conducted in order to examine the role of the hepatic vagus nerve in insulin response after intraperitoneal injections of 0.1 and 0.3 g/kg of glucose. Measurements were made 5 days after section of this branch. In a first experiment, arterial glucose and insulin concentrations were not affected by the hepatic vagotomy following injections of either 0.1 or 0.3 g/kg of glucose. The same finding was also found in a second experiment in which portal glucose and insulin levels were measured after injection of 0.1 g/kg of glucose. These results suggest that large changes in neural activity are needed for the hepatic vagus nerve to influence the insulin response.
Cardin
S
S
Department of Physical Education, University of Montréal, Québec, Canada.
Lavoie
L
L
Gutierrez
A
A
Bongbélé
J
J
Lavoie
J M
JM
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D007328:Insulin / Q000097:blood*; D008099:Liver / Q000294:innervation / Q000502:physiology*; D008297:Male; D009475:Neurons, Afferent / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D014628:Vagotomy
D001786:Blood Glucose; D007328:Insulin; D005947:Glucose