Relation of antral pH to gastrin release and fundal pH in dogs

Summary and conclusions

Four dogs were prepared with Heidenhain pouches and cannulas placed in the fundus and antrum. Fasting pouch output was measured for 1 hr. Changes in pH in the fundus and pouch, and pouch acid production were then determined while antral pH was varied by perfusion in increasing and decreasing sequences. Results were virtually identical with ascending and descending antral pH values.

With an antral pH below 1.8 no appreciable pouch secretory effect was found, the values being identical with those obtained under fasting conditions. A transition zone was encountered between antral pH 1.8–3.0 in which relatively small and variable amounts of pouch acid were produced. Above an antral pH of 3.0 a significant stimulatory effect was noted that did not increase with further increments of antral pH.

Fundal and pouch pH were relatively high and had little relationship to one another when antral pH was less than 1.8. The values fell and became more closely associated at the antral transition zone of pH 1.8–3.0. Above an antral pH of 3.0, fundus and pouch pH decreased and fluctuated in a parallel manner. Pouch pH was consistently below fundal pH.