A study group headed by the Charité scientists, Joachim Jankowski and Vera Jankowski, has detected a new hormone that constricts the blood vessels, thus increasing blood pressure. In the latest issue of Nature Medicine , the researchers reported the hormone to be the nucleotide "urine adenosine tetraphosphate" (Up4A). They found that Up4A is produced by the endothelial cells, the inner cells of the blood vessel wall, and released into the blood, where it affects the muscle cells of the vessel wall and causes contractions. Constriction of the muscle cells triggers constriction of the vessel walls, which leads to a rise in blood pressure.
"The blood pressure in rats increased by 30% over the long term after injecting Up4A into the animals", reported Joachim Jankowski, a biochemist in the Department of Nephrology and Endocrinology at Campus Benjamin Franklin. "This hormone may be responsible for pathologically high blood pressure", added Prof. Walter Zidek, director of the department.
Clinical studies are underway to test whether the hormone concentration in hypertensive patients is pathologically high. At the same time, the researchers want to develop an antagonist hormone in the lab, which will counteract vasoconstriction.
The causes of pathologically high blood pressure have not yet been clarified. There is no causal therapy. Numerous drugs are available for lowering blood pressure, which target different areas like the endogenous blood pressure-increasing hormone angiotensin (ACE inhibitors, angiotensin receptor blockers), calcium flow into the vascular muscles (calcium antagonists) or salt levels in the body (diuretics). However, it is still not clear whether these drugs also remedy the underlying causes of hypertension.
In Germany, 60% of the men and 40% of the women between the ages of 25 and 74 years suffer from high blood pressure.
(24 January 2005)
Dr. Joachim Jankowski can be reached under +49-30-8445-1773 (e-mail firstname.lastname@example.org) or Prof. Walter Zidek under +49-30-8445-2441 (email@example.com) to answer any questions you may have.
(C) 2005 - Charité Berlin
Jankowski V, Tolle M, Vanholder R, Schonfelder G, van der Giet M, Henning L, Schluter H, Paul M, Zidek W, Jankowski J.
Uridine adenosine tetraphosphate: a novel endothelium- derived vasoconstrictive factor.
Nat Med. 2005 Jan 23
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