excxp
Bluelighter
http://www.scripps.edu/newsandviews/e_20040927/janda.html
Antibodies are usually produced only in response to large molecule invaders such as proteins, not to small drug molecules. Glycation acts like a linker that allows [the methamphetamine] to be displayed to the immune system, triggering a vaccine-like reaction.
The crux of our finding is that methamphetamine can react with glucose and proteins to form what are called a "glycated" product. Additionaly, we showed that the presence of these methamphetamine-glycated proteins in the bloodstream can lead to a response from the immune system, stimulating the production of antibodies that recognize the glycated form of methamphetamine. This immune response might be one way that the body acquires resistance and may have implications for why methamphetamine addicts go on long binges. If the antibodies prevent some of the drug from reaching its place of action in the brain, addicts might require more of the drug because some of it is bound up by antibodies. What this suggests is that since methamphetamine may react with proteins and induce an immune response; perhaps the body naturally has the ability to generate antibodies that may counteract methamphetamine. If the mechanism we are proposing is correct, then addicts are in essence vaccinating themselves against the drug when they use it and thus exposing themselves to ever-increasing amounts of methamphetamine in order to achieve a high. Amphetamines in general are capable of this type of chemistry, but not all drugs of abuse. It is the molecular structure of the drug that determines if "glycation" is possible. Our initial studies into this area were with a long-lived nicotine metabolite, nornicotine, which can also participate in protein glycation. The two compounds possess similar molecular structures. Thus, our study does not necessary provide new "cautions" as methamphetamine is already known to be highly addictive and heavy use leads to tolerance, but instead, provides a previously unrecognized mechanism for why methamphetamine users develop tolerance.
