New treatments for patients with spinal cord injuries may become possible one day, as scientists have shown unexpected and extensive natural recovery after spinal cord injury in primates.
Researchers at the University of California studied adult rhesus monkeys and found that that connections between circuits in the spinal cord re-grew spontaneously and extensively, restoring fully 60 percent of the connections 24 weeks after a mild spinal cord injury.
"The number of connections in spinal cord circuits drops by 80 percent immediately after the injury," said Ephron Rosenzweig of the University of California.
"But new growth sprouting from spared axons - the long fibers extending from the brain cells, or neurons, which carry signals to other neurons in the central nervous system - restored more than half of the original number of connections," said Mr. Rosenzweig.
More profoundly, the spontaneous recovery was accompanied by extensive recovery of movement on the affected side of the body.
Mark H. Tuszynski, neurologist at the Veterans Affairs San Diego Health System, said the team is now investigating how the nervous system is able to generate so much natural growth after injury.
This knowledge could lead to development of drugs or genes that could transmit high-growth signals to spinal cord damage sites after more severe spinal cord injury.
The findings were published in the online edition of Nature Neuroscience .
