DOE National Lab Research Shows What Happens in the Brain after a Head Injury and Suggests Totally New Treatment Approach
A team of scientists used radiotracer imaging technology to show what happens to the brain during the first hours after a head injury. It has been known for some time that immediately after injury there is a large outflow of glutamate, a chemical neurotransmitter essential for learning and memory in the normal brain. Excess stimulation of receptors for glutamate can kill the hyper-activated nerve cells. Therefore, drugs that can block glutamate receptors were developed for the treatment of brain injury. However, this approach has failed in thousands of head injured subjects enrolled in several large clinical studies. This new imaging study explains this failure by showing that the window of opportunity for effectively blocking the receptors is very short (less than one hour), and is followed by an extended period in which the receptors are under-stimulated and treatment with a glutamate-receptor stimulating drug at this point greatly improved memory function. Thus for the first time we know, said Dr. Biegon, that actively stimulating brain cells after injury is beneficial rather than detrimental to recovery. Under DOE support, this research was performed at Lawrence Berkeley National Laboratory by Dr. Anat Biegon before she moved to Brookhaven National Laboratory. This study was published in the April 6, 2004, issue of Proceedings of the National Academy of Sciences and has been the subject of recent news media stories including NBC news (September 14, 2004).