Discovery of nitric oxide delivery mechanism may point to new avenue for treating high blood pressure
November 14, 2012 in Medical research
(Medical Xpress)—Researchers at the University of Virginia School of Medicine have shed new light on blood pressure regulation with the discovery of an unexpected mechanism by which hemoglobin controls the delivery of nitric oxide. The findings may point to a new therapeutic target for treating high blood pressure and may have far-reaching implications for many organ systems and illnesses.
Hemoglobin is best known for its role in transporting oxygen in the blood. But it also can bind nitric oxide, a powerful vasodilator. By relaxing smooth muscle cells, nitric oxide widens blood vessels, decreasing blood pressure. The new U.Va. research shows that there is a complete system within the myoendothelial junction – the "bridge" between the smooth muscle and the endothelial cells lining the blood vessel walls – that allows hemoglobin to regulate nitric oxide delivery, essentially controlling the size of the blood vessel.
The U.Va. researchers were surprised to spot hemoglobin alpha in the myoendothelial junction. At first they thought it was a mistake. "We didn't believe it. We thought it was contamination," said researcher Brant Isakson, an associate professor of molecular physiology and biological physics. "Maybe we had a blood smear on our fingers? … Then we started to put two and two together."
What they found has earned them a place in the pages of the prestigious journal Nature.
The U.Va. team had seen reports of hemoglobin alpha from other researchers looking at myoendothelial junctions. But it would typically be one protein in a list of many, reported for the sake of completeness. The U.Va. researchers, however, realized hemoglobin alpha was actually regulating the binding of nitric oxide, directly affecting the size of the blood vessel.
"To make a complicated story short, we did find it binds the nitric oxide, and it can bind it very tightly or loosely," Isakson said. "Basically, what we have in this very localized structure is a complete system for regulating nitric oxide delivery to the smooth muscle."
Some chronic problems with high blood pressure, Isakson suspects, may be the result of problems with the amount of hemoglobin in the blood vessel wall.
"The implications for this research are very widespread. The most immediate thing is blood pressure regulation," Isakson said. "We're trying to find ways to specifically delete hemoglobin alpha in the blood vessel wall and look at blood pressure changes."
But the mechanism the U.Va. researchers have identified may play an important role in many other parts of the body, and possibly in many illnesses. "There are all these scattered reports of hemoglobin and [nitrogen oxide signaling] expressed in the lungs, for example, and in neurons, and in all these other places. Maybe, just maybe, it's very similar to what we show here: That they form this macromolecular complex and that can very tightly regulate how much nitric oxide is delivered," Isakson said.
"In our case, we're very interested in how that nitric oxide regulates blood pressure and dilates the smooth muscle. But you can extrapolate that to neurons. Neurons use nitric oxide for their cell communication," he said. "Inflammatory responses, there's another big one. Nitric oxide is anti-inflammatory. We're really extrapolating here, but if we are correct, if you can regulate how much nitric oxide is released by this complex, then you can regulate the inflammatory response."
More information: The findings have been published by Nature online and will appear in a forthcoming print edition.
Journal reference:
Nature
Provided by
University of Virginia
-
Reducing side-effects of painkillers
Sep 12, 2006 |
not rated yet |
0
-
Researchers discover powerful molecule regulator in blood pressure control system
Mar 11, 2010 |
not rated yet |
0
-
Nitric oxide impacts source of sickle cell pain crisis
May 09, 2011 |
not rated yet |
0
-
Nitric oxide-releasing wrap for donor organs and cloth for therapeutic socks
Jan 06, 2010 |
not rated yet |
0
-
Inhaling nitric oxide eases pain crises in sickle cell patients
Oct 19, 2010 |
not rated yet |
0
-
Motion perception revisited: High Phi effect challenges established motion perception assumptions
Apr 23, 2013 |
3 / 5 (2) |
2
-
Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update)
Apr 02, 2013 |
4.5 / 5 (11) |
5
-
The visual system as economist: Neural resource allocation in visual adaptation
Mar 30, 2013 |
5 / 5 (2) |
9
-
Separate lives: Neuronal and organismal lifespans decoupled
Mar 27, 2013 |
4.9 / 5 (8) |
0
-
Sizing things up: The evolutionary neurobiology of scale invariance
Feb 28, 2013 |
4.8 / 5 (10) |
14
-
Why is zone 1 in liver more prone to ischemic injury?
May 23, 2013
-
How can there be villous adenoma in colon, if there are no villi there
May 22, 2013
-
How can there be a term called "intestinal metaplasia" of stomach
May 21, 2013
-
Pressure-volume curve: Elastic Recoil Pressure don't make sense
May 18, 2013
-
If you became brain-dead, would you want them to pull the plug?
May 17, 2013
-
MRI bill question
May 15, 2013
- More from Physics Forums - Medical Sciences
More news stories
Study reveals new mechanism for estrogen suppression of liver lipid synthesis
By discovering the new mechanism by which estrogen suppresses lipid synthesis in the liver, UC Irvine endocrinologists have revealed a potential new approach toward treating certain liver diseases.
Medical research
May 23, 2013 |
5 / 5 (1) |
0
|
MRI-based measurement helps predict vascular disease in the brain
Aortic arch pulse wave velocity, a measure of arterial stiffness, is a strong independent predictor of disease of the vessels that supply blood to the brain, according to a new study published in the June issue the journal ...
Medical research
May 23, 2013 |
not rated yet |
0
Antibiotics: A new understanding of sulfonamide nervous system side effects
Since the discovery of Prontosil in 1932, sulfonamide antibiotics have been used to combat a wide spectrum of bacterial infections, from acne to chlamydia and pneumonia. However, their side effects can include serious neurological ...
Medical research
May 23, 2013 |
3 / 5 (1) |
0
|
Scientists discover molecule triggers sensation of itch
Scientists at the National Institutes of Health report they have discovered in mouse studies that a small molecule released in the spinal cord triggers a process that is later experienced in the brain as ...
Medical research
May 23, 2013 |
5 / 5 (3) |
0
|
Discarded immune cells induce the relocation of stem cells
Spanish researchers have discovered that the daily clearance of neutrophils from the body stimulates the release of hematopoietic stem cells from the bone marrow into the bloodstream, according to a report published today ...
Medical research
May 23, 2013 |
5 / 5 (2) |
0
First drug to improve heart failure mortality in over a decade
Coenzyme Q10 decreases all cause mortality by half, according to the results of a multicentre randomised double blind trial presented today at Heart Failure 2013 congress. It is the first drug to improve heart failure mortality ...
Hormone levels may provide key to understanding psychological disorders in women
Women at a particular stage in their monthly menstrual cycle may be more vulnerable to some of the psychological side-effects associated with stressful experiences, according to a study from UCL.
Heart failure accelerates male 'menopause'
Heart failure accelerates the aging process and brings on early andropausal syndrome (AS), according to research presented today at the Heart Failure Congress 2013. AS, also referred to as male 'menopause', was four times ...
Researchers identify first drug targets in childhood genetic tumor disorder
Two mutations central to the development of infantile myofibromatosis (IM)—a disorder characterized by multiple tumors involving the skin, bone, and soft tissue—may provide new therapeutic targets, according to researchers ...
Going live: Immune cell activation in multiple sclerosis
Biological processes are generally based on events at the molecular and cellular level. To understand what happens in the course of infections, diseases or normal bodily functions, scientists would need to ...
Feds fight morning-after pill age ruling in NY
(AP)—Department of Justice lawyers have again asked a federal appeals court in New York to delay lifting age restrictions and prescription requirements on an emergency contraceptive popularly known as the morning-after ...
Nov 14, 2012
Rank: not rated yet
This may have the potential to positively affect many disease states.