A simple method to record parietal cells in the fundic mucosa in baboons.

BACKGROUND Gastric parietal cells in a baboon were recently found to be auto-fluorescent. AIM To study gastric sections with a fluorescent microscope in a cohort of baboons. MATERIAL AND METHODS Gastric sections from 38 baboons were stained with hematoxylin-eosin (H&E) and examined in a fluorescence microscope (FLM). The thickness of the parietal cell population was assessed at x 10 magnification. RESULTS H&E stained all mucosal cells: fovelar, parietal and chief cells. When the same sections were analyzed with an FLM, only parietal cells were auto-fluorescent, whereas fovelar and chief cells remained non-fluorescent. Parietal cells formed a distinct, continuous auto-fluorescent band. The ratio of the auto-fluorescent parietal cell band/total mucosa ranged between 0.20 and 0.30. CONCLUSION Gastric parietal cells became auto-fluorescent when H&E-stained sections from baboon stomachs were observed with an FLM. Eosin was the stain responsible for this optical phenomenon.