Mice that had strokes recovered more quickly if they received low doses of the common sleep aid zolpidem, according to researchers at the Stanford University School of Medicine.
Until now the drug (which is sold in Britain as Ambien) has never been definitively shown to enhance stroke recovery.
The study’s senior author, Gary Steinberg, cautions that the study’s results need to be independently replicated in other laboratories before clinical trials of the drug’s capacity as a stroke-recovery agent can begin.
Stroke affects 110,000 people in England every year. It is caused by a blockage of blood supply to the brain, which is treatable, but only if drugs are administered within hours of the stroke occurring. It is estimated that fewer than 10 per cent of stroke patients benefit from medical intervention.
No pharmacological therapy has been shown to improve stroke recovery after the event. The study’s authors say that physical therapy has only been shown to be ‘marginally successful’.
The researchers say that Ambien enhances a type of nerve-cell signalling activity which appears to benefit stroke patients. In the study, this signalling was increased even when the drug was given at doses well below that at which it has a sedative effect.
The researchers administered the drug three days after the stroke to ensure that any benefit observed was resulting from an effect on brain recovery, rather than from the drug preventing initial tissue damage from the stroke.
The researchers subjected test mice to two kinds of tests; one measured the speed with which they removed a patch of adhesive tape from one of their paws. The other test gauged their ability to traverse a horizontal rotating beam.
In almost every case, mice treated with Ambien recovered at a faster rate than control mice did. It took about a month, for example, for mice not given the drug to fully recover their stroke-impaired ability to notice the tape stuck to their paw. Mice given Ambien recovered that ability within a few days of treatment.