Marijuana. Good for the Brain?

Drugs are bad for you. Rats can tell you. Scientists are giving them drugs all the time.

Most recreational drugs, such as alcohol, nicotine and cocaine, have been shown to suppress this new growth of nerve cells. We kind of need new nerve cells. Xia Zhang of the University of Saskatchewan in Saskatoon, Canada, and colleagues decided to see what effects a synthetic cannabinoid called HU210 had on rats' brains.

Gosh, were they in for a spurprise. They found that giving rats high doses of HU210 twice a day for 10 days increased the rate of nerve cell formation, or neurogenesis, in the hippocampus by about 40%.

But there's more!

When the rats who had received the cannabinoid were placed under stress, they showed fewer signs of anxiety and depression than rats who had not had the treatment. When neurogenesis was halted in these rats using X-rays, this effect disappeared, indicating that the new cell growth might be responsible for the behavioural changes.

For those curious, THC (D9-tetrahydrocannabinol) does not seem to have the same effect.

And speaking of rats, who wants to visit the Karni Mata Temple in Deshnoke, India with me? The rats who live there are considered holy because they are believed to be reincarnations of people hiding from the wrath of Yama, the Hindu god of death. Hundreds of thousands of them teem together--and stink together--throughout the temple.

The rats are fed milk and meal, which pilgrims drink and eat afterward. It's considered a blessing to eat food drenched with rat saliva. It's considered very lucky to spot a white rat.

Many people throughout the world are as fond of rats as the Hindus. They keep rats in their homes, snuggle with them, kiss them and devout entire websites to them. The Rat and Mouse Club of America has clubs and chapters where people gather touting the virtues of rodents.

Learn everything you may never have wanted to know about rats here.