A team of researchers at the University of Copenhagen have found medicinal cannabis could help reduce essential tremor, a neurological disorder that causes involuntary and rhythmic shaking, most often in the hands.

Using a mouse model, the team discovered that an injection with the synthetic cannabinoid WIN55,212-2 prompts astrocytes in the spinal cord to release adenosine, a substance which then reduces nerve activity and undesired shaking.

Previous research into medicinal cannabis has focussed on the nerve cells, the so-called neurons, rather than the impact of medicinal cannabis on astrocytes.

Voluntary and spontaneous movements are triggered when the spinal cord’s motor neurons are activated. The motor neurons connect the spinal cord with the muscles, and each time a motor neuron sends impulses to the muscles, it causes contraction and thus movement.

Involuntary shaking occurs when the motor neurons send out conflicting signals at the same time, which is why researchers have focussed on the spinal cord up to now.

The new approach will avoid affecting the neurons in the brain responsible for our memory and cognitive abilities, and doctors would be able to offer patients effective treatment without the most problematic side effects of medical cannabis.

The study is published in Nature Neuroscience.