High concentration of estrogen inhibits secretion of

Options

A. FSH
B. Gn RH
C. Prolactin
D. Both 1 & 2

Answer

To solve the question "High concentration of estrogen inhibits secretion of," we will analyze the effects of estrogen on various hormones.

### Step-by-Step Solution:

1. **Understand the Role of Estrogen**:
- Estrogen is a key hormone in the female reproductive system, particularly involved in the regulation of the menstrual cycle and reproductive processes.

2. **Identify the Hormones in the Options**:
- The options provided are:
1. FSH (Follicle Stimulating Hormone)
2. GnRH (Gonadotropin-Releasing Hormone)
3. Prolactin
4. Both 1 and 2

3. **Analyze the Effects of High Estrogen Levels**:
- High levels of estrogen are known to exert negative feedback on the hypothalamus and pituitary gland.
- This feedback mechanism leads to the inhibition of the secretion of GnRH from the hypothalamus and FSH from the anterior pituitary.

4. **Evaluate Each Option**:
- **Option 1 (FSH)**: High estrogen levels inhibit FSH secretion. This is correct.
- **Option 2 (GnRH)**: High estrogen levels also inhibit GnRH secretion. This is correct.
- **Option 3 (Prolactin)**: Prolactin is primarily involved in milk production and is not directly inhibited by estrogen in the same manner. This is incorrect.
- **Option 4 (Both 1 and 2)**: Since both FSH and GnRH are inhibited by high estrogen levels, this is also correct.

5. **Conclusion**:
- The correct answer is **Option 4**, which states that high concentrations of estrogen inhibit the secretion of both FSH and GnRH.

### Final Answer:
High concentration of estrogen inhibits the secretion of both FSH and GnRH (Option 4).

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