A new study conducted by scientists at the Stanford University Medical Center found that low doses of the popular sleeping aid zolpidem, known by its trade name Ambien, helped mice rebound from strokes much faster than those that did not receive a dose. Strokes cause initial damage when part of the brain's blood supply is blocked and this damage occurs within the first few hours. Although drugs and mechanical devices for clearing this blockage are available, they must be initiated within a short period of time after the onset of the stroke, making them beneficial to less than 10 percent of stroke patients.
In the current study, scientists administered low, sub-sedative doses zolpidem, which enhances synaptic signaling of the GABA receptor — the main inhibitory neurotransmitter in the brain — three days after the stroke in order to guarantee that any effects they observed where from the drug's effects on brain recovery. In one group of mice, they induced strokes that damaged sensory ability, and in the other they induced strokes that impair movement. Each group was administered a regimen of zolpidem or a control solution without the drug.
The results showed that in almost every case, mice treated with zolpidem recovered from their stroke-induced impairment at a significantly faster rate than the control mice. Mice untreated with zolpidem took approximately one month to recover from their impairment, as opposed to only a few days for mice treated with zolpidem.
"Before this study, the thinking in the field was that GABA signaling after a stroke was detrimental," said Gary Steinberg, who oversaw the research, in a press release. "But now we know that if it's the right kind of GABA signaling, it's beneficial. And we've identified an FDA-approved drug that decisively promotes the beneficial signaling."
The results open up new possibilities for stroke treatment and will push researchers to further investigate the role of GABA in stroke recovery.
The findings were published in the Dec. 18 issue of Brain.
