Samatostatin (GHIH) is secreted by

Options

A. Pituitary
B. Thyroid
C. Pineal
D. Hypthalamus.

Answer

**Step-by-Step Solution:**

1. **Understanding Somatostatin (GHIH)**: Somatostatin, also known as Growth Hormone Inhibiting Hormone (GHIH), is a peptide hormone that plays a crucial role in regulating the endocrine system and inhibiting the secretion of other hormones.

2. **Identifying the Source of Secretion**: The question asks where somatostatin is secreted from. The options provided are pituitary, thyroid, pineal, and hypothalamus.

3. **Analyzing Each Option**:
- **Pituitary Gland**: The pituitary gland is known as the master gland because it releases various hormones, but it does not secrete somatostatin. Therefore, this option is incorrect.
- **Thyroid Gland**: The thyroid gland primarily produces hormones like thyroxin, which regulates metabolism. It does not produce somatostatin, making this option incorrect as well.
- **Pineal Gland**: The pineal gland secretes melatonin, which regulates sleep cycles. It does not secrete somatostatin, so this option is also incorrect.
- **Hypothalamus**: The hypothalamus is a crucial part of the brain that regulates the pituitary gland's hormone secretion. It is responsible for producing somatostatin, which inhibits the release of growth hormone from the pituitary gland.

4. **Conclusion**: Based on the analysis, the correct answer is that somatostatin (GHIH) is secreted by the hypothalamus.

**Final Answer**: Somatostatin (GHIH) is secreted by the hypothalamus.

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