Gastric Acid Secretion Research Paper

1456 Words 6 Pages
The gastrointestinal tract is significant to proper everyday functions. A large process in this region of the body is gastric acid secretion. This secretion occurs from a number of different mechanisms. However, this process is largely contrived through two means, parietal cells and drugs. Utilized each day in processes like digestion and metabolism, the role parietal cells and drugs play in regulating gastric acid secretion is fundamental to life.
Gastric Acid Secretion by Parietal Cells
Gastric acid aids digestion by creating the optimal pH for pepsin and gastric lipase and by stimulating pancreatic bicarbonate secretion. Acid secretion is initiated by food: the thought, smell, or taste of food effects vagal stimulation of the gastrin-secreting
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Acid in the stomach functions to kill bacteria, and aid digestion by solubilizing food. The acid is also important to establish the optimal pH (between 1.8 and 3.5) for the function of the digestive enzyme pepsin. Stimulation of acid secretion involves the translocation of H+/K+-ATPases to the apical membrane of the parietal cell. When the cell is resting (not stimulated), H+/K+-ATPases are located in vesicles inside the cell. When the cell is stimulated, these vesicles fuse with the plasma membrane, thereby increasing the surface area of the plasma membrane and the number of proton pumps in the membrane. Acetylcholine and histamine directly stimulate parietal cells to increase acid secretion. Gastrin stimulates acid secretion by stimulating histamine release from ECL cells. When the pH of the stomach gets too low, somatostatin secretion is stimulated. Somatostatin inhibits acid secretion by direct effects on parietal cells, and also by inhibiting release of the positive regulators histamine and gastrin. The balance of activity of the different regulators changes as food is consumed and passes through different segments of the upper GI …show more content…
Yet, this bodily process is a key contributor to normal everyday functions, particularly metabolism and digestion. Gastric acid secretion is precisely regulated by neural (acetylcholine), hormonal (gastrin), and paracrine (histamine; somatostatin) mechanisms. The prime inhibitor of acid secretion is somatostatin. Its inhibitory paracrine effect is mediated predominantly by receptors coupled via guanine nucleotide binding proteins to inhibition of adenylate cyclase activity. All the pathways converge on and modulate the activity of the luminal enzyme, H+, K+-ATPase, the proton pump of the parietal cell. Parietal cells are essential to gastric secretion. Precise information on the mechanisms involved in gastric acid secretion and the identification of specific receptor subtypes has led to the development of potent drugs capable of inhibiting acid secretion, including proton pump inhibitors, H2 blockers, and prostaglandins. Gastric acid secretion is a vital process to everyday human and animal living, even though not many really take the time to understand and appreciate its essential purpose in the body. And without this modulation process, the actions between eating and excreting could be widely different from how it is known

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