Saturday, July 26, 2008

Fly through a mouse brain!

What do you do when you want to see what is inside a mouse's head?

In the past, you had to:
1. Find a mouse.
2. Kill said mouse.
3. Remove brain (the mouse's, not your own).
4. Fix brain (even if it wasn't broken to begin with) in formaldehyde or some other chemical.
5. Embed brain in wax.
6. Cut brain into teeny tiny slices.
7. Try to get one of those slices to sit flat on a slide.
8. Stain the brain slice.
9. Look at it under an expensive microscope.
10. Try to figure out what you are looking at.

Now, through the wonders of modern Interwebology, you need not go through the toil and trouble and smell. Now we have The Mouse Brain Library. For the librarians among my loyal readership, this is not the kind of library where you walk through the stacks until you find a brain on the shelves that might look interesting, then check it out with your library card.

No, indeed. This is the kind of library that lets you look inside a mouse's brain without leaving the comfort of your favorite coffee shop. You can even watch movies.

Here's my favorite. It's a trip through a mouse head, starting at the top and going down. This one shows structure of the surrounding head, as well as the brain. The nose is to the right and the back of the head is to the left. You can see the eyes, white circles at the top and bottom of the image. Between them lie the olfactory bulbs, responsible for smell. (The sense of smell that is. The smelliness comes from the other end of the mouse.) You can also see the spiraling chambers of the nasal cavities.

And that ends our tour through a mouse's head. I hope you enjoyed it. Watch your step as you leave the tour bus.

Tuesday, July 15, 2008

Yeah, but what happens if you smoke it?

A compound in oregano and basil has been shown to have antiinflammatory effects in mice. The compound, called (E)-beta-caryophyllene or(E)-BCP, is also found in large amounts in rosemary, cinnamon, and black pepper. And Cannabis sativa, a.k.a. marijuana.

The most well-studied components of marijuana, cannabinol and tetrahydrocannabinol (THC), exert their effects by binding to two receptors, CB1 and CB2. CB1 is expressed in the brain and other tissues and is responsible for the ...elevating...effects of Cannabis sativa. CB2, on the other hand is primarily found in tissues outside the brain. Activation of CB2 has been shown to inhibit inflammation.

This paper describes some experiments showing that (E)-BCP binds to CB2, but not CB1. They did all the stuff you are supposed to do in the lab to demonstrate its binding qualities, then they tested the compound in mice.

They dissolved (E)-BCP in (appropriately) olive oil and fed it to mice. Then they injected the footpads of the mice with carrageenan, which makes the footpads swell. The feet of the mice that had been fed (E)-BCP had much less swelling than the mice that had been fed olive oil alone. This antiinflammatory effect was not found when they used mice in which the CB2 receptor had been knocked out, demonstrating that it was the CB2 receptor activation that was responsible for the beneficial effect.

I knew pesto pizza had to be good for you.

Tuesday, July 1, 2008

Did they make it to the top?

Here's a story in the Philadelphia Inquirer about the murine Everest ascent.
Here's a blog about it.
Here's some video.

The answer: almost.
The real answer awaits the arrival of the mouse blood from Nepal...and some lab work. Not as glamorous as mountain climbing, I know, but that's science for you.