Radiothelemetric monitoring of hydrogen ion levels of the small intestine.

A radiotelemetric technique was used to document the pH level within the intact small intestine of the dog. It was found that the pH in the area of the upper part of the jejunum ranged in a neutral zone between 6 to 7 in the fasting dog. Stimulation of the Thiry-Vella loop in these dogs, with either acid or alkaline solution, always resulted in the pH rising toward a higher level, the highest pH level being recorded as 8.2. All dogs demonstrated a lowering of this pH level toward a neutral range of 6 to 7 within three hours after Thiry-Vella loop challenge.