Changes in Morphology and Cellular Replacement of Surface Epithelia in Human Gastric Mucosa Affected by Different Pathological Changes: A Scanning Electron Microscopical Study of Human Gastric Biopsy Material

Abstract

The surface epithelium of normal gastric mucosa shows a constant turnover, migrating from the proliferation zone at the neck of the gastric glands to the mucosal surface. The cytologic changes associated with the concomitant cellular differentiation were so far studied in sections by light and electron microscopy only. With these methods neither the changes of surface morphology associated with cellular maturation nor the shedding of surface epithelia can be recorded. With the scanning electron microscope it is possible to study especially these changes of the mucosal surface plus those of the single surface epithelia over a wide range of magnification and with a sufficient depth of focus. In this study therefore an attempt was made to correlate some scanning electron microscopic findings concerning these changes of mucosal and cellular surface with the results of parallel light microscopic examinations. For this purpose double biopsies of human gastric mucosa were taken during routine endoscopic examination. One of these biopsies was processed for light microscopic examination after formaldehyde fixation. The other was fixed in buffered glutaraldehyde solution and 1 % OS04 solution and thereafter the material was processed for scanning electron microscopic study by dehydration against an increasing acetone gradient, critical point drying and sputter coating of the dry specimens which were mounted on metal stubs with conductive silver. Some aspects of surface morphology of the mucosa and the single cells in correlation to different types of gastritis are demonstrated and the morphological expressions of cytological degeneration and shedding from the mucosal surface are commented on.