Which of the following statements is correct?

Options

A. Some tranquillizers function by inhibiting the enzymes which catalyse the degradation of noradrenaline
B. Tranquillizers are narcotic drugs
C. Tranquillizers are chemical compounds that do not affect the message transfer from nerve to receptor
D. Tranquillizers are chemical compounds that can relieve pain and fever.

Explanation

To determine which statement about tranquilizers is correct, we will analyze each option provided:

1. **Option 1**: Some tranquilizers function by inhibiting the enzymes which catalyze the degradation of norepinephrine.

- **Analysis**: This statement is true. Tranquilizers can inhibit the enzymes that break down norepinephrine, which is important for mood regulation. By preventing the degradation of norepinephrine, tranquilizers can help maintain its levels in the brain, thus alleviating symptoms of stress and depression.

2. **Option 2**: Tranquilizers are narcotic drugs.

- **Analysis**: This statement is false. While both tranquilizers and narcotics are used in medicine, they serve different purposes. Narcotics primarily relieve pain, while tranquilizers are used to reduce anxiety and stress.

3. **Option 3**: Tranquilizers are chemical compounds that do not affect the message transfer from nerve to receptor.

- **Analysis**: This statement is also false. Tranquilizers do affect the message transfer from nerve to receptor by modulating neurotransmitter levels, particularly norepinephrine and others, which are crucial for communication between nerves.

4. **Option 4**: Tranquilizers are chemical compounds that can relieve pain and fever.

- **Analysis**: This statement is incorrect. Tranquilizers are not primarily used for pain relief or fever reduction; they are specifically used to treat anxiety and stress-related conditions.

**Conclusion**: The correct statement is **Option 1**: Some tranquilizers function by inhibiting the enzymes which catalyze the degradation of norepinephrine.