Navigation Links
Blood vessels: The pied piper for growing nerve cells
Date:4/10/2008

Researchers at Johns Hopkins have discovered that blood vessels in the head can guide growing facial nerve cells with blood pressure controlling proteins. The findings, which suggest that blood vessels throughout the body might have the same power of persuasion over many nerves, are published this week in Nature.

Were excited to have stumbled across another family of proteins that can tell a growing nerve which way to grow, says David Ginty, Ph.D., a professor of neuroscience at Hopkins and investigator of the Howard Hughes Medical Institute. But the really interesting thing is that the nerves appear to use blood vessels as guideposts to direct their growth in one of several possible directions.

The research team studied in mice a group of about 15,000 nerve cells known as the superior cervical ganglia, or SCG, which extend projections that innervate various structures in the head including the eyes, mouth and salivary glands. The SCG sits in a Y-like branching point of the blood vessel in the neck that supplies the head with blood, the carotid artery. In the developing embryo, nerve projections grow out of the SCG and grow along one of the two branches of the carotid artery; the nerves that grow along the internal carotid innervate the eyes and mouth among other head structures, and those that grow along the external carotid innervate the salivary glands.

To figure out how nerve cells choose to grow along the external carotid artery to innervate the salivary glands, the team looked for genes that appear to be preferentially turned on in the external carotid, and off in the internal carotid. Says Ginty, Theres only two directions they can go and we wanted to know if they choose their direction or if the decision to go one way or the other is random.

They found one gene that is expressed preferentially in the external carotid, a gene that makes the blood pressure regulating protein, endothelin, active. It comes as no surprise that something critical for regulating the cardiovascular system in the adult also is used for directing nerve growth in the developing embryo, says Ginty. The genome is limited and nature has figured out a way to use things over and over again for unrelated functions.

Further examination of the arteries in mouse embryos confirmed that endothelin is found only in the external carotid. To confirm that the nerve cell projections grow toward endothelin, the researchers removed SCGs and grew each one next to an endothelin-soaked bead. Checking on them three days later, the team found that nerves from the SCGs had grown towards the beads. To be certain that endothelin directs nerve growth in the living animal, the researchers then looked in mice that had the endothelin gene removed. Sure enough, these mice had no nerves growing along their external carotid arteries.

The team then wondered if all growing nerves in the SCG can respond to endothelin. So they looked for the endothelin receptors in SCG nerves and found only a subset of SCG nerves make endothelin receptors and concluded that those nerves somehow already had been chosen to respond to the endothelin made by the external carotid.

How do these nerve cells know which target organ theyre supposed to innervate when they all come from the same progenitor? asks Ginty. This is what were going to study next.


'/>"/>

Contact: Audrey Huang
audrey@jhmi.edu
410-614-5105
Johns Hopkins Medical Institutions
Source:Eurekalert

Related medicine news :

1. Cholesterol, blood pressure control may reverse atherosclerosis in adults with diabetes
2. Aggressive Cholesterol, Blood Pressure Treatment Shows Some Benefit
3. Microwave treatments for enlarged prostate cause blood pressure surges
4. Blood pressure enzyme can have tumor-sensing role
5. Stem cell research leads to potential new therapy for rare blood disorder
6. Gator Blood May Be New Source of Antibiotics
7. Leaky blood vessels open up nerve cells to toxic assault in Lou Gehrigs disease
8. Tight Backpack Straps Cut Blood to Shoulders, Arms
9. One-Third of Dementia Cases Laid to Small Blood Vessel Damage
10. Significant dementia risk attributable to small blood vessel damage
11. Lowering Blood Pressure Improves Brain Hemorrhage Outcomes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2017)... ... June 22, 2017 , ... Plastic Surgery Associates is ... Top Doctor for 2017. Each year, research and information firm, Castle Connolly, releases their ... title in 2015, this marks the 3rd time that Dr. Canales has ...
(Date:6/22/2017)... ... June 22, 2017 , ... ... grant from the American Heart Association (AHA) to launch a Rheumatic Heart Disease ... the prevention and diagnosis of rheumatic heart disease (RHD) in high-risk, financially disadvantaged ...
(Date:6/22/2017)... ... June 22, 2017 , ... Vighter, a premier ... received certification for ANSI/ASIS PSC.1-2012. The company’s work in countries throughout Southwest Asia, ... of law has been degraded. The PSC.1 standard was created to protect fundamental ...
(Date:6/20/2017)... Tennessee (PRWEB) , ... June 20, 2017 , ... ... care services, announced today that Claritas Capital, a Nashville-based private equity firm, has ... accelerate our expansion plans for some time, and Claritas Capital offers the smart ...
(Date:6/20/2017)... ... 2017 , ... After months of negotiations, FaceCradle USA is proud to announce the debut of ... , “Introducing our product on QVC is something we all worked hard to achieve for ... more than 90 million homes in the United States,” said FaceCradle USA President Dylan Doherty. ...
Breaking Medicine News(10 mins):
(Date:6/10/2017)... BESSEMER, Ala. , June 9, 2017  Shane K. Burchfield, ... Member recognized for excellence as a Podiatrist in Alabama ... of Podiatry at Family First Foot Care. He brings over 20 ... sports medicine, pain management and healthcare, to his role. ... Family First Foot Care, PC is pleased to welcome ...
(Date:6/8/2017)... , June 8, 2017  StatLab ... leading developer and manufacturer of diagnostic supplies ... today that Cressey & Company LP ("Cressey ... has completed a growth-focused investment in the ... majority ownership position from selling shareholder, Prairie ...
(Date:6/5/2017)... , June 5, 2017 Kohll,s Pharmacy ... the United States . The Raizer is ... a fallen person up to an almost-standing position ... and operated by one assistant and does not ... is simple enough that a child can operate it, ...
Breaking Medicine Technology: