The first article is about a study on rats where they removed the brain and kidneys and looked for mercury after they were poisoned and treated. I have no idea how this is relevant because the article doesn't say enough to make sense. How did they know the amount of mercury in the rat's brain before they cut it open? It was merely a 7 day treatment and they don't even say if it was oral or injection. It has nothing to do with chronic, long term exposure and poisoning - it implies a deliberate acute poisoning, nothing comparable to what we have. And if you look at the article I cited below, you'll see that one of the guys whose name is on this article is listed on another paper saying DMSA does accelerate mercury elimination from the brain.
http://www.ncbi.nlm.nih.gov/pubmed/12870874
The second article doesn't explain why they say the chelators are inefficient at removing mercury from the brain. They don't say if it was oral or injectable administration of the chelators and I still don't see how a pretreated, mercury poisoned rat is comparable to us.
http://www.ncbi.nlm.nih.gov/pubmed/2539660
The third article doesn't explain anything, either. They say neither DMSA nor DMPS forms a true chelate complex with mercuric ions but so what? They say these drugs should be considered "suboptimal" but if they just concluded they don't form a true chelate complex, then why are they only "suboptimal" rather than "completely ineffective"? Like the first two articles you listed, it doesn't make sense.
http://www.ncbi.nlm.nih.gov/pubmed/15310232
Here's a paper about DMSA:
http://www.google.com/url?sa=t&rct=..._yN_ziAAmnG35T29Q&sig2=poBHiF6Hal58lRC8akxUgQ
Aposhian, one of the names listed in the first article, is also a name on a paper entitled "DMSA and DMPS, Water Soluble Antidotes for Heavy Metal Poisoning" where he quotes "DMSA accelerated Hg elimination from the brain, but DMPS had no effect." And "The mercury content of the kidney, liver, and brain of mice or guinea pigs exposed to MeHgBr was decreased by posttreatment with DMSA (6). These experiments were extended (47) to show that smaller amounts of DMSA could be used, greater delay before treatment was possible, and DMSA was effective po. In addition, DMSA was shown to be four times more effective than D-pen for increasing the urinary excretion of mercury. Rats poisoned with MeHg preferred to drink water containing DMSA (2.5 mg/ml) rather than water without it "."
I'm not going to go on and list a bunch of sites that say DMSA crosses the BBB because what's the point? I'm trusting the word of a doctor with 20+ years of firsthand experience rather than a google educated guess. I will know for sure when I do it what it will do. If I can eventually stop taking the ADH hormone at night and stay off it, and my hormones and everything else normalizes, then I'll know the DMSA cleared mercury from my brain.
As for all the bad side effects I've read about, I think most of them happened because people started chelation without being in the proper condition to do it. People need a CDSA test to make sure the liver and intestines are in good enough shape. For instance, any attempt at chelation by a person who has leaky gut syndrome will result in mercury redistribution instead of elimination and is guaranteed to mess them up badly. And you can have leaky gut syndrome with dysbiosis and not know it - the symptoms can be vague and not even point to the GI tract as a source of the problem. That's what happened to me. It took me 4 years to completely get over leaky gut with a very aggressive diet and supplement plan. I've been preparing for chelation literally for years.