Final answer:
Antidiuretic hormone (ADH), also known as vasopressin, helps to increase blood pressure by constricting blood vessels and promoting water reabsorption in the kidneys, which is crucial in the case of decreased blood volume due to a hemorrhage.
Step-by-step explanation:
Jeremiah has a state of decreased blood volume due to a hemorrhage. A hormone that can help in such a situation by increasing blood pressure is antidiuretic hormone (ADH), which is also referred to as vasopressin. This hormone has a characteristic of constricting blood vessels. In addition to this, ADH aids in water reabsorption in the kidneys by activating aquaporin channels in the collecting ducts, which increases overall fluid levels and helps restore blood volume and pressure.