Augusta, Ga. Dr. David Pollock has a simple message for fellow hypertension researchers: think endothelin.
In a country where better than 30 percent of adults have high blood pressure and 50-75 percent of those have salt-sensitive hypertension, he believes the powerful endothelin system, which helps the body eliminate salt, should not be essentially ignored.
However, the research and clinical world focus on suppressing a better-known system, which prompts the body to hold onto salt, said Pollock, Chief of the Section of Experimental Medicine at the Medical College of Georgia at Georgia Regents University.
Pollock is giving the 2013 Lewis K. Dahl Memorial Lecture Sept. 14 during the American Heart Association's High Blood Pressure Research 2013 Scientific Sessions in New Orleans.
"If you look at blood pressure regulation and salt-controlled sodium excretion, everybody sees the renin-angiotensin-aldosterone system. That is what the books say." Pollock said. No doubt the system is important. When blood volume is low, the kidneys secret renin to make the hormone angiotensin. Angiotensin drives blood pressure up by promoting sodium retention directly and by stimulating release of aldosterone, a hormone that prompts the kidneys to resorb sodium rather than eliminate it in the urine.
It's a protective system intended to ensure that the body has enough sodium to keep blood pressure at sufficient levels to sustain life. It's also a system that's somehow dysregulated in some hypertensive patients who take ACE inhibitors or angiotensin receptor blockers to turn it down.
Since most Americans already turn down this system by eating too much salt, Pollock argues that enhancing sodium excretion might be a better approach, particularly for those not responding to existing therapies.
In fact, when an animal on a high-salt diet is given a drug to block endothelin's B receptor, blood pressure goes up 50 points
|Contact: Toni Baker|
Medical College of Georgia at Georgia Regents University