When fat is in the stomach the secretion of gastrin is inhibited. This inhibition is due to

Options

A. Presence of fat
B. Non-stimulation of vagus
C. Slow digestion of fat
D. Release of enterogastron

Explanation

**Step-by-Step Solution:**

1. **Understanding Gastrin:** Gastrin is a hormone produced by the stomach that stimulates the secretion of gastric acid, which aids in digestion.

2. **Effect of Fat in the Stomach:** When fat is present in the stomach, it triggers a series of physiological responses. One of these responses is the inhibition of gastrin secretion.

3. **Mechanism of Inhibition:** The presence of fat in the stomach leads to the activation of receptors that signal the body to slow down gastric activity. This is due to the fact that fats take longer to digest compared to carbohydrates and proteins.

4. **Role of the Duodenum:** The duodenum is the first part of the small intestine that receives partially digested food from the stomach. When fat enters the duodenum, it releases hormones that signal the stomach to reduce its activity.

5. **Anterior Gastric Reflex:** The anterior gastric reflex is a mechanism by which the presence of fat and acid in the duodenum inhibits gastric secretions and motility. This reflex is essential to prevent the stomach from overwhelming the duodenum with too much food too quickly.

6. **Hormonal Regulation:** The hormone responsible for this inhibition is known as the "anterior gastric hormone," which is secreted by the mucosa of the duodenum. This hormone inhibits gastric movements and secretions, thereby reducing gastrin levels.

7. **Conclusion:** Therefore, the inhibition of gastrin secretion when fat is present in the stomach is primarily due to the release of the anterior gastric hormone from the duodenal mucosa.

**Final Answer:** The inhibition of gastrin secretion when fat is in the stomach is due to the release of the anterior gastric hormone.

---