AJP - Gastrointestinal and Liver Physiology, Vol 241, Issue 5 349-G358, Copyright © 1981 by American Physiological Society

ARTICLES

Ultrastructural changes related to functional activity in gastric oxyntic cells

J. G. Forte, J. A. Black, T. M. Forte, T. E. Machen and J. M. Wolosin

When stimulated to secrete HCl the gastric oxyntic cell undergoes profound morphological change. The identifiable apical cell surface is greatly expanded in the stimulated oxyntic cell as compared with nonsecreting ones. To account for this change, one hypothesis proposes that the expanded surface is derived from the fusion of cytoplasmic tubulovesicular membranes with the existing limited apical membrane surface. An alternative hypothesis suggests that the tubulovesicular compartment is actually confluent with the apical surface at all times and that the morphological appearance follows the expansion of this supercollapsed compartment as HCl secretion commences. A variety of morphological evidence is reviewed here including transmission electron microscopy during various stages of secretion and inhibition, analysis of freeze-fracture replicas, penetration of macromolecular tracers, and membrane surface-staining characteristics. It is concluded that the weight of evidence favors a membrane fusion process. Moreover, recent comparative studies of membrane fractions from resting and secreting stomachs show different morphological and functional properties that are also consistent with a fusion hypothesis as a fundamental event in the membrane transformation of the oxyntic cell.

This article has been cited by other articles:

				L. Zhu, Y. Liu, and J. G. Forte Ezrin oligomers are the membrane-bound dormant form in gastric parietal cells Am J Physiol Cell Physiol, June 1, 2005; 288(6): C1242 - C1254. [Abstract] [Full Text] [PDF]

				R. Zhou, C. Watson, C. Fu, X. Yao, and J. G. Forte Myosin II is present in gastric parietal cells and required for lamellipodial dynamics associated with cell activation Am J Physiol Cell Physiol, September 1, 2003; 285(3): C662 - C673. [Abstract] [Full Text] [PDF]

				R. Zhou, Z. Guo, C. Watson, E. Chen, R. Kong, W. Wang, and X. Yao Polarized Distribution of IQGAP Proteins in Gastric Parietal Cells and Their Roles in Regulated Epithelial Cell Secretion Mol. Biol. Cell, March 1, 2003; 14(3): 1097 - 1108. [Abstract] [Full Text] [PDF]

				J. G. Duman, N. J. Pathak, M. S. Ladinsky, K. L. McDonald, and J. G. Forte Three-dimensional reconstruction of cytoplasmic membrane networks in parietal cells J. Cell Sci., March 15, 2002; 115(6): 1251 - 1258. [Abstract] [Full Text] [PDF]

				D. A. Ammar, P. N. B. Nguyen, and J. G. Forte Functionally distinct pools of actin in secretory cells Am J Physiol Cell Physiol, August 1, 2001; 281(2): C407 - C417. [Abstract] [Full Text] [PDF]

				X. Zhou, S. Nakamura, S.-L. Xia, and C. S. Wingo Increased CO2 stimulates K/Rb reabsorption mediated by H-K-ATPase in CCD of potassium-restricted rabbit Am J Physiol Renal Physiol, August 1, 2001; 281(2): F366 - F373. [Abstract] [Full Text] [PDF]

				T. Sonnentag, W.-K. Siegel, O. Bachmann, H. Rossmann, A. Mack, H.-J. Wagner, M. Gregor, and U. Seidler Agonist-induced cytoplasmic volume changes in cultured rabbit parietal cells Am J Physiol Gastrointest Liver Physiol, July 1, 2000; 279(1): G40 - G48. [Abstract] [Full Text] [PDF]

				B. H. Hirst Parietal cell membrane trafficking Focus on "Expression of rab11a N124I in gastric parietal cells inhibits stimulatory recruitment of the H+-K+-ATPase" Am J Physiol Cell Physiol, September 1, 1999; 277(3): C359 - C360. [Full Text] [PDF]

				C. T. Okamoto, S. M. Karam, Y. Y. Jeng, J. G. Forte, and J. R. Goldenring Identification of clathrin and clathrin adaptors on tubulovesicles of gastric acid secretory (oxyntic) cells Am J Physiol Cell Physiol, April 1, 1998; 274(4): C1017 - C1029. [Abstract] [Full Text] [PDF]

				J. G. Forte, B. Ly, Q. Rong, S. Ogihara, M. Ramilo, B. Agnew, and X. Yao State of actin in gastric parietal cells Am J Physiol Cell Physiol, January 1, 1998; 274(1): C97 - C104. [Abstract] [Full Text] [PDF]