$376 Wednesday, November 9, 2005 Poster Abstracts

tasks. Tasks explored the ability to suppress reflexive saccades as task demands increased; the generation of express (very fast.) and anticipatory saccades and the ability to respond to changes in task demand during a saccadic 'oddball ' task. The PD group was able to maintain fixation as well as controls, even in the presence of visual distractors. However, the PD group demonstrated failures of response suppression (i.e. inappropriate reflexive saccades) as task demands increased. A deficiency in inhibitory control is also likely to underpin the increased number of express and anticipatory saccades exhibited by the PD group. The greater nmnber of response selection errors in the PD group, during the oddball task, may also be explained by deficiencies of inhibitory control. These findings are consistent with fronto-striatal pathophysiology influencing the suppression and selection of eye movements.

1088 Predictors of Driving Assessment Outcome in Parldnson's Disease

Worringhaln, C 1, Wood, j2, Kerr, G a, Silburn, pC,3.1School of Human Movement Studies, Queensland University of Technology, Brisbane, Australia; ~ Sehool of Optometry, Queensland University of Technology, Brisbane, Australia; 3Neurology Department, Princess Alexandra Hospital, Brisbane, Australia

Introduction: Clinical decisions about driving can be particularly difficult in Parkinson's Disease (PD), since patients have a range of fluctuating cognitive, motor, and sensory symptoms that, alone or in combination, potentially impair driving. Tiffs study evaluated selected clirfical and functional tests as predictors of driving safety outcomes in PD patients. Methods: Twenty five PD patients and 21 age-matched controls, all regular drivers, underwent neurological evaluation and assess- ment of cognitive, visual and motor function and a standardised, on-road driving assessment. The capacity of the tests to predict pass/fail driving outcomes was determined by selecting a sub-set with the lffghest predictive value from each domain and then sub- jecting these to discriminant function analysis. Accuracy, sensi- tivity, specificity and positive and negative predictive values were determined. Results: Three relatively simple tests from the larger battery predicted pass/fail driving outcomes with relatively high specificity (PD: 64.3°,5, controls: 93.8"/0, both combined: 85.2°,5); and moderate sensi- tivity (PD: 72.7%, controls: 60.0%, both combined: 63.2%). The tests assessed motor performance (Purdue Pegboard test), contrast sensitivity (Pelli-Robson test) and cognitive function (oral version of Symbol Digit Modalities test). Adding time since diagnosis increased specificity to 71.4 °,5 and sensitivity to 90.9°,5 for the PD group. Conclusion: These simple tests confer more objectivity and predictive power to clinical recommendations for driving; they reflect distinct functions that are necessary for safe driving and may be especially useful when on-road assessments are not available.

1089 Non-motor Flucluations in Patients with Paxkinson's Disease: Frequency, Disablement, and Association with MIBG Scintigraphy

Yanagflmra C, Wada Y, Nishimura Y. Nishi-Kobe Medical Center, Kobe, Japan

Object: Nonmotor fluctuations (NMt0, classified as dysautonomic, sensory/pain, and cognitive, are as frequent and disabling as motor fluctuations in Parkinson's disease (PD). Besides, la~I-Metaiodoben- zylguanidine (MIBG) cardiac scintigraphy is a sensitive tool for the detection of autonomic dysfunction in PD. To assess N M F in PD, the relationship between prevalence of N M F and the reduction in cardiac MIBG uptake was studied.

Methods: Fifty-four outpatients with PD were questioned about any non-motor symptoms associated with off periods. Mini-mental state examinations were used to exclude patients rulable to answer the question. Beck's depression scale and UPRRS II and III were used to check the depression status and motor symptoms. MIBG myocardinal uptake was measured in N M F patient groups and other PD groups. Results: Thirty patients had motor fluctuations and all of them had had at least one type of NMF. Some N M F s were observed during "on" as well as "ofF' periods. N M F s were classified as; autonomic (sweating, hot sensation, constipation, abdominal bloating, abdominal pain, palpitation, bladder dysfunction, coughing, leg and foot edema), sensory (pain in lower limbs, paresthesia, internal tremors) and cognitive (depression, amxiety). The H/M ratio and regional MIBG uptake in the PD patients groups with autonomic N M F decreased siglffficantly compared with the ratios in other patient groups. Contusion: N M F s are disabling and not rare in PD patients. Timely recognition of these symptoms can help avoid unnecessary tests. The decrease in MIBG cardiac uptake is related to autonomic NMFs and useful for the detection of non-motor symptoms.

1090 Voltanttlletl'ie measurement of striatal dopainine release induced by physiological stil~luli and trace amine nlhnetics

Kenji Yoshimi ~'l'~, Taizo Nakazato ~, Kazue Takahata 3, Seiichiro Shimazu ~, Akira Komatsu 4, Nobutaka Hattori 1, Yoshikuni Mizuno 1. 1DEF. Neurology and Physiology; ~Juntendo Univ. School of Medicine; 3Research Institute of Fujimoto Pharma. Inc.; 4Dep. Physiology, Tokyo Women's Biedical Univ

Background: In-vivo voltammetry make it possible to estimate changes in extracelhilar doparnine level with sub-second time resolution. Method: Time course of striatal extracelhilar doparnine of free-moving rats was measured at carbon-fiber microelectrode implanted chroni- cally in the striatum. Results anti Contusion: Electrical burst stimulation of ascending doparnine fibers (medial forebrain bundle) induced transient (about 4 sec of duration) elevation of extracelhilar dopamine. When animals are under food deprivation, food pellet induced quick elevation of extracellular dopamine and it reduced to the basal level after the end of food consmnption. The time course of this food response took about 10 man. Tiffs is direct evidence that the nigro-striatal dopamine system is assodated with reward as well as mesolimbic system. Enhancement of dopamine release by trace amine and synthetic analogue was evaluated with this in-vivo voltammetric system. Phenylethylamine (PEA, 100 mg/kg sc) elevated extracellular dopa- mine. A trace amine mimetics (-)-1-(benzofuran-2-yl)-2-propylanffno- pentane (BPAP), enhanced dopanffne release at lower dose (11-3 mg/kg so). BPAP does not have affinity to doparnine receptors, but enhance monoamine release and block monoarnine uptake. BPAP has been shown to improve motor dysfunction of reserpnie-treated rats and MPTP-treated monkeys. Our results suggest enhancement of physio- logical dopanffne release by trace amine mimetics can be a new therapeutic strategy for Parkinson's disease.

1091 Possibility for neurogenesis in s~bstantia nigra of Parkinsonian brain

Kenji Yoshimi ~, Yong-RJ Rell ~, Tatsmlori Seki ~, Masafunli Onodera ~, Hideki MoclffzukJ i, YostffkUlff Mizmlol. Dep. 1Neurology and :Anatomy, Yuntendo Univ. School of Medicine, 2-1-1 Hongo, Bunkyo-lcu, To]cyo l13-8d21, Japan; 3Dep. Hematology, Univ. Tsz&uba, Tsukuba, Ibaraki, 305-0005 Japan

Background: Possible nigral neurogenesis in animals and autopsy brains was evaluated. Since antidepressants enhance neurogenesis in the hippocampus, neurogenetic therapy may possible in other neurodegenerative diseases.