Approximately 50 million people nationwide have high blood pressure, but less than one third of them have it under control, according to the American Heart Association. Hypertension is considered a major risk factor for cardiovascular problems such as heart attack and stroke. Civelli and his colleagues found that urotensin II constricts arteries more mildly and for a longer period of time than other chemicals known for similar effects on blood pressure. In addition, the researchers found that urotensin II is manufactured in the kidney, indicating that this organ plays an important role in how the protein regulates blood pressure. Once a receptor finally binds to a chemical, researchers then determine what the chemical looks like and how it functions.
Receptors act as the gateway between nerve cells.
When bound to a specific chemical, they stimulate nerves to fire off their own neurotransmitters, which can initiate certain behaviors or inhibit others. Receptors also can act as a gateway between blood vessels and nerve cells, binding with chemicals in the body that in turn stimulate nerve cells to constrict or loosen blood vessels. The researchers are now focusing on learning how the receptor helps blood vessels and the brain control blood pressure. Pinpointing how urotensin II interacts with the wide range of neurotransmitters, proteins and other chemicals that work to maintain normal blood pressure could result in more effective treatments for high blood pressure, Civelli said. Civelli has been conducting research on receptors in the nervous system for more than a decade.