Acute changes in extracellular fluid volume modify the antroduodenal flow of saline in dogs: a possible physiological role.

The antroduodenal (AD) flow of saline was measured in anesthetized dogs following two different protocols of acute changes in extracellular fluid (ECF) volume. ECF expansion by iv infusion of saline before or after hemorrhage decreased the AD flow; conversely, hemorrhage before or after expansion increased flow. These alternating modifications in the AD flow are independent of the sequence of volemic changes and may constitute part of the homeostatic responses of the gut to confront life-threatening situations such as accidental hyperhydration or hemorrhage.