New drugs: The discovery of a molecular "dimmer switch" may allow fine control over this system, leading to a "new generation of drugs", the science festival was told.
Natural cannabis-like substances produced in the body, called endocannabinoids, have similar effects on pain relief and appetite as cannabis itself, explained Prof Roger Pertwee, an expert in neuropharmacology from Aberdeen University.
Cannabis has been used as a medicine over many centuries, said Prof Pertwee.
"However, this floods the whole system.
"These drugs could be much more selective."
Selective adjustment could lead to much more specific treatments for different conditions, he said.
An anti-obesity drug that blocks this system should be released next year, Prof Pertwee went on.
The drug acts centrally on the brain, to reduce the feeling of reward that is obtained from eating sweet foods.
It also works peripherally by reducing the accumulation of fat, he explained.
However, the new finding of a molecular "dimmer switch" could allow doctors in future to turn up or down sensitivity to these endocannabinoids, instead of simply blocking them.
The "switch" is found on the endocannabinoid receptor.
"We now have the equivalent to a volume control on the receptor," he explained.
"We should now be able either to boost the signal or dampen it down."
Such drugs, known as allosteric enhancers, have been developed for other conditions in the past, said Prof Pertwee. Valium is a common example of an allosteric enhancer, although it works on a very different receptor, he said.
Dampening the signal could help treat obesity in a similar way to the new drug which blocks the pathway.
However, there are many diseases, such as multiple sclerosis, cancer and some cardiovascular diseases, which may benefit instead from a boost to this system, he believes.
For example, this "dimmer switch", or allosteric enhancer, has potential as a new class of pain relief, Prof Pertwee explained.
Other conditions that may benefit from this discovery include post-traumatic stress disorder and binge eating disorders, according to Prof Pertwee.
"The work so far is very much working with bits of tissue.
"We are yet to see what happens in whole animals or humans," Prof Pertwee admitted.