Researchers from the Imperial College London found that the drug called prazosin prevented memory loss in mice showing signs of Alzheimer's disease.
Previous studies have shown how blood pressure drugs can prevent Alzheimer's from occurring as well as slowing its progression, the Daily Express reported.
High blood pressure is one of the known risk factors for developing Alzheimer's.
Fast and effective communication between brain cells is essential for the normal functioning of the brain and is orchestrated by chemical messengers called neurotransmitters.
The neurotransmitter noradrenaline, as well as several others, can become disrupted in particular areas of the brain during Alzheimer's.
The team set out to investigate whether drugs that affect the action of noradrenaline could provide benefits in mice showing features of Alzheimer's.
They tested a range of compounds in the laboratory and found that the drug prazosin, which can be used to relax blood vessels in people with high blood pressure, also showed potential for reducing signs of Alzheimer's.
The researchers then used the drug to treat mice bred to develop a build-up of the Alzheimer's protein amyloid in their brain.
These mice showed a decline in memory performance which is characteristic of the disease in humans.
The team found that treatment with prazosin could prevent the memory problems seen in untreated mice.
The drug did not reduce levels of the amyloid protein, but did appear to affect levels of inflammation in the brain. Prazosin boosted the number of brain support cells called astrocytes, which can produce anti-inflammatory proteins.
"We think the drug may stimulate an anti-inflammatory response, and there is increasing evidence that inflammation is a key process in Alzheimer's," Dr Magdalena Sastre, from the Department of Medicine at Imperial College London, said.
The research was published in the journal Neurobiology of Aging.