From the FDA Drug Label
Omeprazole belongs to a class of antisecretory compounds, the substituted benzimidazoles, that suppress gastric acid secretion by specific inhibition of the H+/K+ ATPase enzyme system at the secretory surface of the gastric parietal cell Because this enzyme system is regarded as the acid (proton) pump within the gastric mucosa, omeprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production.
The stomach biochemistry involves the H+/K+ ATPase enzyme system at the secretory surface of the gastric parietal cell, which is responsible for gastric acid secretion. Omeprazole inhibits this enzyme system, thereby blocking the final step of acid production. Key points about stomach biochemistry related to omeprazole include:
- Gastric acid secretion: Omeprazole suppresses gastric acid secretion by inhibiting the H+/K+ ATPase enzyme system.
- Gastric parietal cell: The H+/K+ ATPase enzyme system is located at the secretory surface of the gastric parietal cell.
- Acid production: Omeprazole blocks the final step of acid production by inhibiting the H+/K+ ATPase enzyme system 1.
From the Research
The stomach is a complex biochemical factory that processes food through a combination of mechanical and chemical digestion, with stomach cells producing hydrochloric acid (HCl) and enzymes like pepsin to break down proteins and kill harmful microorganisms, as described in the study by 2. The stomach's biochemical processes are crucial for digestion and overall health. Stomach cells produce hydrochloric acid (HCl), creating a highly acidic environment with a pH between 1.5-3.5, which helps break down proteins and kill harmful microorganisms. The main enzyme in the stomach is pepsin, which is secreted as inactive pepsinogen and activated by the acidic environment to begin protein digestion.
- The stomach also produces gastric lipase to start fat breakdown, though most fat digestion occurs later in the small intestine.
- Mucus-secreting cells protect the stomach lining from being digested by its own acid and enzymes by creating a thick alkaline barrier.
- Gastrin, a hormone produced in the stomach, stimulates acid secretion in response to food intake, as discussed in the study by 3. This biochemical system is regulated through multiple feedback mechanisms that balance acid production with food intake and ensure proper digestion while protecting the stomach from self-digestion.
- Disruptions to this biochemical balance can lead to conditions like gastritis, peptic ulcers, or acid reflux disease, which can be treated with medications such as proton pump inhibitors (PPIs) or H2-receptor antagonists (H2RAs), as studied in 4 and 5. The use of PPIs, such as omeprazole, has been shown to be effective in reducing gastric acid secretion and treating conditions like gastroesophageal reflux disease (GERD), as demonstrated in the study by 3.