Gastric Blood Flow and Mucosal Defense
Any other tissue would rapidly disintegrate if exposed to the corrosive acid that bathes the lining of the stomach. The gastric lining, or mucosa, also resists all but the harshest of miscellaneous chemical insults. It is no surprise, then, that this tissue has intrigued doctors and scientists for centuries, particularly with regard to how it achieves such remarkable Teflon-like chemical resistance properties. It is only relatively recently, however, that the defensive secrets of the gastric mucosa have begun to be appreciated in detail. This chapter describes one of the central elements of the gastric mucosal defensive system, blood flow. It is recognized that blood flow is also pivotal to mucosal restitution and the healing processes. However, the emphasis here is on the role of mucosal blood flow in preventing the initiation of gastric lesions. The reader will also note that other important components of the gastric defensive system are covered in substantial depth in other chapters of this volume. For this reason, only very brief mention of these other important defensive factors will be made here.
KeywordsHemorrhagic Shock Mean Arterial Blood Pressure Gastric Lesion Mucosal Blood Flow Epithelial Cell Layer
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