Cannabis Increasing Ultrasonic Vocalisations and Cat Odour Avoidance in Rats
The University of Sydney have been using government funding to determine the different behaviours of rats affected by marijuana.
Aim:
To demonstrate how anxiety-related behaviour differs in different strains of rats when given cannabis.
Method:
75 day old male Lewis albino rats and Wistar albino rats were group housed in large plastic tubs with eight rats of the same strain per tub.
During the "conditioning phase" rats were placed into a chamber with aluminium walls and 16 metal bars as a floor. The rats received an electric shock for a duration of one second after 2, 4, 6 and 8 minutes, then returned to their home cage. After one hour, different dosages of cannabis were injected intraperitoneally (into the abdomens) and another 30 minutes later they were returned to the chamber for a further ten minutes (but not shocked). During the whole process an ultrasound microphone recorded the rats’ vocalisations.
In another part of the experiment, rats were placed in a larger chamber and exposed to cat odour (on a piece of worn cat collar) for twenty minutes. Their movements were monitored to determine the amount of time they remained in the vicinity of the collar and the amount of time they spent in a hide box. Twenty four hours later the rats were injected with cannabis and returned to the chamber for another twenty minutes to compare avoidance and hiding times with their original exposure.
Conclusion:
The results showed that cannabis promotes anxiety-like behaviour in Wistar rats but not in Lewis rats. They also showed that cannabis magnifies this behaviour when the rats are footshocked or subjected to the presence of cat odour.
Considering the aim of the exercise was to demonstrate differences in effect of two strains of rats, it is highly questionable as to its actual purpose in that how it correlates to human medicine?
The authors mention that cannabis is the most widely used illegal drug in the world. One therefore has to wonder why the human effects are not already known through observation of our own species.
This work was supported by an NHMRC Project Grant
What Can You Do?
Please write to the National Health and Medical Research Council (NHMRC), asking them to stop wasting valuable funding on animal experiments, and to instead fund only human-specific research:
Prof Warwick Anderson
- Chief Executive Officer
- NHMRC
- GPO Box 1421
- Canberra
- ACT 2601
- Email:
And write to the university to express your disappointment of such wasteful and futile research.
Dr Michael Spence
- Vice Chancellor
- University of Sydney
- NSW 2006
- Email: vice.chancellor@sydney.edu.au
- Reference:
Cannabinoids increase conditioned ultrasonic vocalisations and cat odour avoidance in rats: Strain differences in drug-induced anxiety. Jonathon C. Arnold, Robert A. Dielenberg, Iain S. McGrego
Published: Life Sciences 87 (2010) 572-578, Elsevier
