Posted by bleauberry on January 28, 2009, at 17:30:49
In reply to Blood BDNF reflects brain: Potential Treatment, posted by SLS on January 26, 2009, at 16:58:42
I don't know about the BDNF stuff at all so I can't comment on that.
But I did want to comment on studies done on rats or mice.
Rat brains are not human brains. For example, studies that show that the drug DMSA removes mercury from brain tissues were done on rats. The brain barrier of rats is much more permeable than the human blood brain barrier. There is solid evidence DMSA removes rat brain mercury, but zero evidence it removes human brain mercury. And with this particular example, we are only talking about the brain barrier. We haven't even got to the brain yet. It is wrong to conclude that what happens with a rat is predictive of what happens to a human.
I could go on for a long time picking apart the flawed methods of study done with rats. In short, all of it is based on human assumption. We assume a particular behavior implies a certain thing. Studies that measure actual chemicals in blood or brain of rats, well, again, that does not mean it happens that way in humans. It might or it might not. Since we aren't going to do a biopsy of a live human brain, we can only go by assumption, which again, is not something to place all your bets on.
Whatever BDNF does in rats is in my opinion not reliable to predict what it does in humans. Rats are not humans. Similar, but no cigar. Even apes or monkeys are not a good substitute.
Whenever I see a study that involved rats or mice, I click the X in the corner and move on to the next study. Using a mouse of course. :-)
The human physiology is inherently unique from any other organism on the planet.
poster:bleauberry
thread:876377
URL: http://www.dr-bob.org/babble/20090104/msgs/876854.html