Stimulation of acid secretion of stomach is due to

Options

A. Gastrin
B. Histamine
C. vagal activation
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Acid Secretion in the Stomach:**
- The stomach secretes hydrochloric acid (HCl) which is crucial for digestion. This secretion is regulated by various factors including hormones and nerve signals.

2. **Identifying Key Players in Acid Secretion:**
- The primary hormone involved in stimulating acid secretion is **Gastrin**. It is released by G cells in the stomach lining in response to food intake.
- **Histamine** is another important factor that enhances acid secretion. It is released from enterochromaffin-like cells in the stomach and acts on parietal cells to increase acid production.
- **Vagal Activation** refers to the stimulation of the vagus nerve, which is part of the parasympathetic nervous system. This nerve also plays a role in stimulating acid secretion by signaling the stomach to produce more acid.

3. **Analyzing the Options:**
- **Option A: Gastrin** - Correct, as it directly stimulates acid secretion.
- **Option B: Histamine** - Correct, as it enhances the action of gastrin and stimulates parietal cells.
- **Option C: Vagal Activation** - Correct, as it stimulates acid secretion through the nervous system.
- **Option D: All of the Above** - Since all the listed factors contribute to the stimulation of acid secretion, this option is also correct.

4. **Conclusion:**
- The correct answer to the question is **Option D: All of the Above**, as all three factors (Gastrin, Histamine, and Vagal Activation) play a role in stimulating acid secretion in the stomach.

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