FIG. 1.

Experimental setup. (A) Photograph of the stomach, carefully lifted through a ventral incision, and glued with tissue adhesive to the surface of a bent spatula. There is a sharp borderline between the white surface of the forestomach and the darker (red) surface of the corpus. (B) Schematic drawing of the nanoinjector setup. The collecting pipette is inserted through a small incision in the ventral antrum wall. The sample is collected from the dorsal antrum mucosa penetrating from the luminal side. The abdominal cavity is perfused with a solution similar to blood plasma; the gastric lumen is perfused with a CO₂-saturated isotonic salt solution (pH 3.8).