Which of the statements is incorrect w.r.t. melatonin hormone ?

Options

A. Shows diurnal variation.
B. Antigonadial hormone
C. Secreted by Pineal body
D. Poorly vascularised

Answer

To determine which statement about the hormone melatonin is incorrect, let's analyze each option step by step:

1. **Understanding Melatonin**:
- Melatonin is a hormone produced by the pineal gland, which is located in the brain.
- It plays a crucial role in regulating the sleep-wake cycle and is often referred to as the "sleep hormone."

2. **Analyzing the Options**:
- **Option A: Shows diurnal variation**:
- Diurnal variation means that the levels of the hormone fluctuate based on the time of day. Melatonin levels are typically higher at night and lower during the day, indicating that this statement is correct.

- **Option B: Antigonadial hormone**:
- Melatonin is known to have an effect on the reproductive hormones and can inhibit gonadal function, making it an antigonadial hormone. Thus, this statement is also correct.

- **Option C: Secreted by the pineal body**:
- Melatonin is indeed secreted by the pineal gland (or pineal body). Therefore, this statement is correct as well.

- **Option D: Poorly vascularized**:
- The pineal gland is actually well vascularized, meaning it has a good blood supply. Therefore, the statement that melatonin is poorly vascularized is incorrect.

3. **Conclusion**:
- The incorrect statement regarding melatonin is **Option D: Poorly vascularized**.

### Final Answer:
The incorrect statement with respect to melatonin hormone is: **Option D: Poorly vascularized**.