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<A HREF="http://news.excite.com/news/r/011108/17/health-parkinsons"> Parkinson's Clues Revealed</A> Or; http://news.excite.com/news/r/011108/17/health-parkinsons Autopsies of Parkinson's patients have shown that protein deposits called Lewy bodies form in an area of the brain involved in dopamine production, according to Dr. Peter T. Lansbury, Jr., of Harvard Medical School in Boston, Massachusetts. Whether Lewy bodies are a cause or an effect of the destruction of dopamine-producing neurons has been a mystery, Lansbury told Reuters Health in an interview. He explained that Lewy bodies are made up of abnormal forms of a protein called alpha-synuclein. The normal form of the protein is abundant in the brains of healthy people, but Lewy bodies are made of "fibrils" of the protein. Previously, Lansbury's team found that there is an intermediate stage, the protofibril, that forms during the transformation of normal alpha-synuclein into fibrils. Based on this discovery, Lansbury and his colleagues speculated that the protofibrils might be responsible for the destruction of dopamine-producing neurons. If that were the case, then keeping protofibrils from becoming fibrils might actually lead to greater damage, according to Lansbury. On the other hand, keeping normal alpha-synuclein from becoming protofibrils might prevent the destruction of the dopamine-producing cells, he said. To find out which step of the process--alpha-synuclein to protofibril, or protofibril to fibril--is the damaging one, Lansbury and his colleagues set up a screen to identify drug-like molecules that block one phase of the process. During this screen, they found that "dopamine and L-dopa as well as many relatives all seem to block the second step" of the process, Lansbury said. "That shocked us," the Harvard researcher said. It seems that dopamine forms a complex with alpha-synuclein, a step that prevents the formation of fibrils and allows a build-up of damaging protofibrils. The research may "allow people to take rational strategies to improve effectiveness of L-dopa," Lansbury said. It may be possible to modify L-dopa, which the brain converts to dopamine, to prevent the formation of these complexes, he said. ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn