A patient complains of constant thirst, excessive passing of urine and low blood pressure. When the doctor checked the patients blood glucose and blood insulin level, the level were normal or slightly low. The doctor diagnosed the condition as diabetes insipidus. But he decided to measure one more hormone in patients blood. Which hormone does the doctor intend to measure?

Explanation

To solve the question regarding the patient's condition and the hormone the doctor intends to measure, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Symptoms**: The patient is experiencing constant thirst, excessive urination, and low blood pressure. These symptoms are indicative of a condition related to fluid balance and possibly hormone regulation.

2. **Consider the Diagnosis**: The doctor diagnosed the patient with diabetes insipidus. This condition is characterized by an inability to concentrate urine due to a deficiency of the hormone vasopressin (also known as antidiuretic hormone or ADH).

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