Norepinephrine

Norepinephrine is a hormone and neurotransmitter produced by the adrenal glands and nervous system that regulates heart rate, blood pressure, and stress response. A plasma norepinephrine test measures circulating levels of this compound. Elevated levels may indicate stress, hypertension, or certain tumors (pheochromocytoma), while low levels can suggest autonomic nervous system dysfunction. This test is often used to evaluate blood pressure abnormalities and suspected hormonal disorders.