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Pain is a complex and unpleasant sensation, which some people feel more acutely than others - and its origins remain largely a mystery.

Now, scientists have created 'pain in a dish' by converting skin cells into sensitive neurons in a bid to learn more about these sensations.

The lab-created nerve cells respond to a range of different kinds of pain stimulation, including physical injury, chronic inflammation and cancer chemotherapy.

Scientists have created 'pain in a dish' by converting skin cells into sensitive neurons (illustrated) in a bid to learn more about its origins. In the future, the research could be used to develop better pain-relieving drugs

And in the future, the custom-made neurons could be used to investigate the origins of pain and develop better pain-relieving drugs.

The work follows years of unsuccessful attempts to produce nerve cells from embryonic stem cells, which are immature 'blank slate' cells with the potential to become any tissue in the body.

A turning point came with the development of technology that allowed ordinary skin cells to be reprogrammed into 'induced' stem cells. 

The scientists dubbed the complex process 'transcription-mediated lineage conversion of fibroblasts.'

A team, led by Dr Clifford Woolf at Harvard Medical School, used a cocktail of so-called transcription factors, which are proteins that control the activity of genes.

They were used to transform mouse and human skin cells directly into pain-sensing neurons.

The researchers, whose findings are reported in the journal Nature Neuroscience, were able to model pain hypersensitivity experienced by people who donated skin cells to the study.

'I think the ability to make human pain neurons for the pain field is going to be very important,' Dr Woolf said.

'Furthermore, our failure with embryonic stem cells lead us to work with adult tissue samples, making the technology much more clinically relevant since these are easy to collect from patients suffering from different kinds of pain.'

The researchers produced so-called 'nociceptors', which are sensory nerve endings that respond to potentially damaging stimuli by sending pain signals to the spinal cord and brain.

Nociceptors are found in any area of the body that can sense painful stimuli, such as the skin and muscles. 

The laboratory-generated nerve cells respond to a range of different kinds of pain stimulation, including physical injury (illustrated with a stock image), chronic inflammation and cancer chemotherapy

The cell bodies of the neurons are found in the dorsal root ganglia - for the face - and the trigeminal ganglia for the rest of the body. 

Nociceptors generally only activate following intense, potentially damaging stimuli  - such as a burning sensation. 

They react to provide a protective warning of imminent tissue damage.

But they can become over sensitised after exposure to drugs and chemotherapy, resulting in some people becoming extra sensitive to pain.

The researcher wrote in their paper: 'Our results illustrate how derived neurons with major features of primary nociceptors can be generated and employed as a model for "pain in a dish".'