Johns Hopkins researchers have discovered that a protein involved in blood pressure control can be used to ’steer’ the growth and regrowth of nerve tissue in mice. Nature magazine has a feature article about the phenomena in this month’s issue, and Johns Hopkins has issued a press release.

“We’re 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.