Sydney Science Forum:The Brain on Drugs - Psychopharmacology, the effects of drugs on behaviour
14 September 2011
What is Australia's biggest drug problem? How do people become addicted to drugs? Are party drugs like Ecstasy and Miaow-Miaow really dangerous? Join Professor Iain McGregor, from the University of Sydney's School of Psychology, on an intriguing journey as he answers these questions and introduces you to psychopharmacology - the study of how drugs affect behaviour - in his free Sydney Science Forum talk on 14 September.
Exploring questions on how drugs affect the brain to change mood and behaviour, Professor McGregor will reveal the results of studies on the long-term effects of addictive drugs and alcohol on behaviour and brain function.
Find out whether teenage brains are particularly vulnerable to drug and alcohol-induced damage. Learn about whether addiction to prescription drugs like antidepressants and painkillers really exists and whether party drugs like Ecstasy and Miaow-Miaow are really dangerous. Discover if the cannabis used today is stronger and more harmful to mental health than in the past.
"There's hardly a person in Australia who is not impacted by drug taking - either their own use or that of people around them," said Professor McGregor.
"I'll be talking about the effects of illicit drugs such as cannabis, MDMA - ecstasy, Miaow-Miaow - mephedrone, and synthetic cannabis-like drugs such as Spice and Kronic. I'll also talk about some of our work in developing new antidepressant and anti-anxiety drugs, using the findings from research in our own laboratory," said Professor McGregor.
"Popular party drugs that produce feelings of euphoria, enhanced communication and closeness to others, may have long-term effects on the brain linked to depression, anxiety and cognitive deficits. Our lab has an extensive program of research focused on such effects of party drugs.
"Cannabis is the most widely used illicit drug in the world, yet many of its effects are still quite mysterious. We've been looking at various behavioural and neural effects of cannabis-like drugs - cannabinoids - including the 'brain's own cannabis', a substance called anandamide," explained Professor McGregor.
"There's so much still to understand about how cannabis works in the body, for example, we know that THC from cannabis lodges in fat, so when someone loses weight or exercise, re-intoxication from THC can occur. We discovered this re-intoxication effect in rats and are now doing the first human studies, with people fasting overnight to mobilise fat and also exercising, to see how the re-intoxication effect works in humans."
Professor McGregor's lab is working for the NSW Police on analysing the strength of current cannabis, using 200 samples of cannabis collected by police.
"To determine how strong the cannabis is, we're looking at nine different cannabinoids in the plants including THC and another one called cannabidiol (CBD), that modulates the effects of THC," explained Professor McGregor.
"One concern is that modern hydroponic cannabis is very low in CBD and this may lead to a great adverse impact on mental health among smokers."
Professor McGregor's group has also found a potentially important link between taking drugs and oxytocin release in the brain.
"Oxytocin is called the 'love hormone' - it gives us all those positive feelings associated with social bonding, sex, love and maternal behaviours. We found that taking ecstasy releases oxytocin. But oxytocin overall tends to inhibit drug intake.
"Rats given oxytocin tend to lose interest in alcohol and methamphetamine and become more interested in other rats," said Professor McGregor.
"There's also a connection between oxytocin release in childhood, from having lots of parental love, and being less likely to develop drug addiction later in life. So it looks like there's a link between the amount of loving oxytocin that the growing brain is exposed to and developing drug addiction."
The team have found synthetic oxytocin-like molecules that could potentially be used to treat or prevent drug addiction in humans, by being administered as a nasal spray.
"I'm also interested in the development of animal models of anxiety disorders and depression and in the pharmacological treatment of these disorders," said Professor McGregor.
"There haven't been many new antidepressant and anti-anxiety drugs released since the 1950s - the pharmaceutical industry is very conservative and risk-averse. So my lab is working on new drug development in this area, because some of the current prescription drugs can have greater side effects than beneficial effects.
"There is immense uncertainty as to whether antidepressants do any good, especially for people with mild depression. So it's really important for us to understand the long-term effects of these prescription drugs, especially in light of the fact that there's been an explosion in the use of these drugs in Australia recently. Antidepressant use is up 40% in Australia over the past six years."
In his Sydney Science Forum, Professor McGregor will also contemplate how we will use drugs in the future, such as new uses in creating alternative realities or in aiding learning.
"Psychopharmacology is such a vibrant and fast moving area. My research has been driven by my curiosity in how and why people develop drug addiction but also by the important need to develop better drugs for treating mental illness."
Sydney Science Forum - The Brain on Drugs: Psychopharmacology, the effects of drugs on behaviour
Date: Wednesday 14 September 2011
Time: 5:45pm - 6:45pm
Location: Eastern Ave Auditorium, University of Sydney
Contact: Katynna Gill
Phone: 02 9351 6997