by ozierja (584 Posts), Thu Oct 07, 2010 07:51 am
Protein Study May Help Scientists Better Understand Root Of Preeclampsia.
The UK's Telegraph (10/6, Alleyne) reported, "A mechanism in the body that causes high blood pressure has been uncovered by British scientists in a breakthrough that could lead to new treatments for the condition." The team, comprised of researchers from Cambridge and Nottingham University, "discovered the mechanism while studying pre-eclampsia."
It was well understood that "hormones called angiotensins cause the blood vessels to narrow and blood pressure to rise," the UK's Daily Mail (10/7, Macrae) points out. "But angiotensins are usually hidden out of harm's way deep inside a protein and no one know what led them being released." Using "powerful x-rays," the current study authors were able to observe "dangerous oxygen molecules [that] trigger a shape in the protein, allowing the blood pressure-raising hormones to be released."
In other words, "if the protein is oxidized...it changes shape, allowing access to renin and the release of angiotensin I," MedPage Today (10/6, Smith) reported. "Angiotensin I, in turn, is converted to angiotensin II by the angiotensin converting enzyme, or ACE," according to the paper in Nature. "Angiotensin II is known to constrict arteries, and that's why studies of hypertension have focused on ACE and its inhibitors," but the "'initiating and rate-limiting step' in the process is the release of angiotensin I from angiotensinogen," the authors concluded.
I am trying to get the link to the article...coming soon...
From the article:
Specifically, we demonstrate the oxidative switch of angiotensinogen to its more active sulphydryl-bridged form in the maternal circulation in pre-eclampsiaÃ¢â‚¬â€the hypertensive crisis of pregnancy that threatens the health and survival of both mother and child.