Parkinson's disease progression described

BUFFALO, N.Y., Aug 23, 2005 (United Press International via COMTEX) -- University of Buffalo neuroscientists say they've described for the first time how Parkinson's disease progresses.

The scientists determined rotenone, an environmental toxin linked specifically to Parkinson's disease, selectively destroys the neurons that produce dopamine, the neurotransmitter critical to body movement and muscle control.

Microtubules, intracellular highways that transport dopamine to the brain area that controls body movement, are the crucial target, they report.

Damage to microtubules prevents dopamine from reaching the brain's movement center, causing a back-up of the neurotransmitter in the transport system, the researchers found. The backed-up dopamine accumulates in the body of the neuron and breaks down, causing a release of toxic free radicals, which destroy the neuron.

The study appears in the Journal of Biological Chemistry.