Effects of vagotomy or splanchnicotomy on blood insulin and sugar concentrations in the conscious monkey.

Abstract

Conscious, undisturbed monkeys were used to examine the effects of vagotomy or splanchnicotomy on venous serum immunoreactive insulin (IRI) and whole blood sugar concentrations. During fasts of 21 and 89 hr, ablation of either set of nerves had no effect, but in the 2-day period after the 89-hr fast vagotomy was associated with a decrease in IRI levels without a change in sugar concentrations, and splanchnicotomy was followed by lower sugar levels without a change in those of the IRI. Glucose was infused intragastrically after fasts of 17 and 89 hr. Vagotomy but not splanchnicotomy was associated with high, early peaks in the sugar and IRI curves. This may have been due to rapid emptying of the stomach since in another experiment, when intraduodenal infusions were compared with intragastric ones, the same high, early peaks in the sugar and IRI curves were seen after intraduodenal glucose. The importance of these largely negative findings is discussed. (Endocrinology 86: 642, 1970)