Researchers have developed and successfully tested a new tool for studying the neurobiology of depression, attention deficit hyperactivity disorder, and stimulant abuse. Researchers will be able to use the tool, a new radiotracer, to map the location and circulation of a protein that plays a central role in those conditions: the norepinephrine transporter (NET). Drs. Yu-Shin Ding, Jean Logan, and colleagues at Brookhaven National Laboratory screened six molecules to see whether any of them did the things a radiotracer for NET must do: get into the brain, spread to regions of the brain with high concentrations of NET, bind selectively to the protein, and leave the brain in a reasonable amount of time. Of the six, (S,S)-[11C]methylreboxetine (MRB) was by far the best candidate, binding tightly and specifically to NET. The norepinephrine, dopamine, and serotonin transporters are disrupted in depression, attention disorders, and stimulant abuse. Researchers previously developed radiotracers for the dopamine and serotonin transporters; the ability to image all three transporters in the brain will allow researchers to determine the role of each neurochemical in the disorders.
Journal of Neurochemistry 94(2):337-351, 2005. [Abstract]