Mini-hearts grown to study disease
Thousands of miniature human hearts have been grown for medical research by scientists in Scotland.
The tiny balls of heart cells beat together in a dish every two seconds, and the tissue matches that of human heart muscle.
The researchers, at Abertay University, are using them to test potential drugs for an untreatable condition.
The research is being presented at the World Congress on Biotechnology in Valencia, Spain.
The spheres of heart cells were made with stem cells and measure just 1mm (0.04in) across.
Beating heart cells have been made before, but the researchers say this is the first time they have been used to investigate disease.
'Size does not matter'
Lead researcher Prof Nikolai Zhelev told the BBC: "They are indeed human cells, which physiologically are the same as human hearts, in this case the size does not matter.
"We induced diseases in these mini-hearts, which nobody has done yet, in particular heart hypertrophy.
"Not only that we've tested different drugs which prevented heart hypertrophy from developing in these mini-hearts."
Hypertrophic cardiomyopathy is an untreatable condition. The heart muscle becomes thicker and stiffer, making it harder to pump blood around the body.
In extreme cases it can even lead to the heart stopping suddenly.
Prof Zhelev said the hearts would allow researchers to rapidly screen a wide range of chemicals and see which were potential cures.
"We can work now, in one experiment, with 1,000 human hearts and test large amounts of compounds, which you can't do in animals," he said.
The researchers think they have already found one drug, currently used to treat cancer, which might help prevent hypertrophy.