Hmm so whats new :) -----Original Message----- From: Parkinson's Information Exchange Network [mailto:[log in to unmask]] On Behalf Of mschild Sent: Thursday, December 17, 2009 10:00 AM To: [log in to unmask] Subject: Falls in PD Correlate with Cholinergic, not Dopaminergic, Dysfunction Loss of cholinergic function predicts falling in Parkinson's disease, according to a new study, independent of dopaminergic denervation. Seventeen PD patients with a history of falls, 27 PD patients without such history, and 15 controls underwent radioimaging with tracers for cholinergic and dopaminergic activity. Both PD groups had reduced dopaminergic function compared to controls, but were not significantly different from each other. Compared to controls, combined cortical and thalamic cholinergic function was reduced in PD non-fallers (-6.6%) and was even worse in fallers (-12.3%). The same pattern held true for cortical function alone. In contrast, thalamic cholinergic function was reduced compared to controls only in fallers. "Thalamic acetylcholinesterase activity derives mainly from terminals of brainstem pedunculopontine nucleus neurons that play a role in the generation of movement," the authors state, "and loss of AChE is likely to reflect PPN neuron dysfunction or degeneration. Our results are consistent with a key role for the PPN in the maintenance of balance in humans and with PPN dysfunction/degeneration as a cause of impaired postural control and gait in PD." They suggest that cholinergic therapy may have a role to play in treatment of gait disorder in PD, but "it is uncertain whether the current generation of cholinesterase inhibitors have sufficient brain penetrance to produce meaningful clinical benefits." History of falls in Parkinson disease is associated with reduced cholinergic activity NI Bohnen, MLTM Muller, RA Koeppe, SA studenski, MA Kilbourn, KA Frey, RL Albin Neurology 2009;73:1670-1676 ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn