For decades, scientists have known that nerve cells in the brain communicate with each other through high-speed contacts called synapses. Now, researchers at Oregon Health Sciences University's Vollum Institute and the University of Oxford have discovered that synapses also are used to communicate with other specialized brain cells called oligodendrocytes. Studying these previously unknown synapses may provide a key for understanding brain function in health and disease. These results appear in the May 11 edition of the journal Nature.
Oligodendrocytes produce myelin, a sheath that surrounds and insulates nerve fibers.
This insulation allows nerve fibers to transmit signals at high speed, like the signals from spinal cord to the muscles of the leg. The breakdown of myelin around these nerve fibers is believed to be the cause of multiple sclerosis. Scientists at OHSU, in collaboration with colleagues at the Medical Research Council Unit at Oxford, have found that the oligodendrocytes taking part in this communication are in their immature stage and do not produce myelin. Previous work has shown that glutamate, the chemical used to transmit signals at these synapses, can inhibit the development of these cells into the mature, myelin-producing oligodendrocytes. These newly discovered connections may help answer many remaining questions about how nerve cells regulate myelin formation.