Two University of Adelaide pharmacologists working with one the worldâ€™s leading neuroscientists have helped pave the way for the development of new pain-killing drugs that are not addictive. US and Australian research team has made a breakthrough in revealing how opioid drugs such as morphine both relieve pain and also cause addiction.
The Adelaide scientists and senior colleagues at the University of Colorado, have isolated in animal models the effect that morphine has on the brainâ€™s immune cells, known as glia, and also on nerve cells (neurons).
Glial cells heighten nerve pain such as sciatica by exciting the neurons that transmit pain signals. While morphine deadens pain by acting at nerve synapses, it also activates glial cells, worsening the drugâ€™s side effects, such as drowsiness, tolerance and addiction.
The scientists tested a new drug called AV411 that blocks morphineâ€™s effects on glia but not on neurons, resulting in effective pain relief without the side effects of addiction.
Doctors prescribe morphine for pain relief but opioids come with the potential for addiction or abuse, tests shows that by blocking morphineâ€™s effects on glial cells, it stops cravings for the drug.