Switching Off Addiction

The discovery of a molecular “addiction switch” in the mammalian brain has the potential to control the addiction process in drug addicts, say U of T researchers Steven Laviolette and Professor Derek van der Kooy of the department of anatomy and cell biology.

A region of the brain called the VTA contains receptors that, when exposed to a certain enzyme, can control the switch from an addicted to non-addicted state and back again. This goes against previous ideas that viewed drug addiction as a permanent change in the brain. The research was published online in Nature Neuroscience.

“Our findings suggest that instead of a permanent alteration in the brain, there’s actually a switch that goes on between two separate systems,” says Laviolette, now a post-doctoral fellow at the University of Pittsburgh. One system mediates the brain’s response to drugs before addiction occurs, and the other mediates response once addiction has set in. “They also suggest we may be able to manipulate that switch pharmacologically to take drug addicts back to a non-addicted state in a relatively short period of time so they do not crave the drug.”