Study on the Phenomenon of Locational Variation in the Speed of Discoloration During the Endoscopic Congo Red Test The Second Report: Ultrastructural Studies on Parietal Cell Populations

: Both quantitative and morphological studies of parietal cells were done in order to investigate the cause of the phenomenon of locational variation in the speed of discoloration during the endoscopic Congo red test. The endoscopic Congo red test was performed in twelve patients with a peptic ulcer and/ or chronic gastritis. In each case, at the times when spotty discoloration was observed, five biopsy specimens were obtained from both the quickly discolored portion (already discolored portion) –Q and the slowly discolored portion (not yet discolored portion) –S of the greater curvature of the middle body at the same time and were separated into two groups (the Q-group and the S–group). Quantitative studies of the parietal cells were performed using the cell isolation method described in our first report. A morphological study was performed with an electron microscope. Two specimens were fixed in glutaraldehyde and osmium tetroxide, and finally embedded in Epon resin. Ultra-thin secretions contrasted with uranyl acetate and lead citrate were viewed with a JEOL-1200EX electron microscope. Each parietal cell was classified according to the classification of ultrastructual stages put forward by Black et al. The number of parietal cells per milligram wet weight of the quickly discolored portion was significantly larger than that of the slowly discolored portion similar to the results of our first report. However the ultrastructural aspects of the parietal cells were not found to be different between the Q–group and S–group portion. It is concluded that the locational variation of the speed of discoloration during the endoscopic Congo red test may be due to the unequal distribution of parietal cells and that the sensitivity and responsiveness of parietal cells to the stimulation may be almost the same in all of the acid secreting area.