Navigation Links
Blood vessels: The pied piper for growing nerve cells

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
Johns Hopkins Medical Institutions

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:
(Date:11/30/2015)... ... November 30, 2015 , ... Newly reviewed and approved “NJ ... graduated from Tufts School of Dental Medicine in 1935. His father graduated from ... family being in dentistry as well as their commitment and passion to the Practice ...
(Date:11/30/2015)... ... November 30, 2015 , ... The ... National Poison Data System (NPDS) reveals that in 2014, someone called a poison ... over two million of which were human exposure cases. , The American Association ...
(Date:11/30/2015)... ... , ... Two years ago, Debbie Gregory, the CEO of, found herself ... Meditation (TM). After encouraging a number of veterans to go through the program, ... the talk. , TM is becoming one of the best alternative treatments for Post-Traumatic ...
(Date:11/30/2015)... ... ... The American Society for Clinical Pathology (ASCP) announced today that it has launched ... ASCP shared its “Give a minute. Get tested. Find a cure.” icon and infographic ... tested for HIV. , ASCP has asked members to replace their Facebook, Twitter, or ...
(Date:11/30/2015)... Beach, FL (PRWEB) , ... November 30, 2015 ... ... of Consumer Reports magazine, quoted Michael Hansen, Ph.D., a senior scientist at Consumer ... and even more so for a child’s exposure limits. , The original Nov ...
Breaking Medicine News(10 mins):
(Date:11/30/2015)... REHOVOT, Israel , Nov. 30, 2015 ... focused on acquiring and developing innovative therapies for ear, ... of Keith A. Katkin as chairman of ... Flesher , chief executive officer for OticPharma, Ltd.  "Keith ... As chairman, he will be able to share this ...
(Date:11/29/2015)...  Strengthening its leadership in connected healthcare informatics, ... IntelliSpace Portal 8.0 , the latest edition of ... helps radiologists detect, diagnose and follow-up on treatment of ... North America Annual Meeting (RSNA) in ... the changing demands in radiology that result from an ...
(Date:11/29/2015)... GE Health Cloud 1 was unveiled today at the ... America (RSNA) meeting in Chicago ... ecosystem and its applications will connect radiologists and clinicians to ... – both inside and outside the hospital setting. ... the digital industrial leader, we are betting big on the ...
Breaking Medicine Technology: