Nigrostriatal function in humans studied with positron emission tomography

✍ Scribed by Dr W. R. W. Martin; M. R. Palmer; C. S. Patlak; D. B. Calne

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 843 KB
• Volume: 26
• Category: Article
• ISSN: 0364-5134
• DOI: 10.1002/ana.410260407

✦ Synopsis

The dopamine depletion that is characteristic of Parkinson's disease has been hypothesized to result from the combination of environmentally induced subclinical damage to the substantia nigra and the age-related loss of additional nigral neurons. Essential to this hypothesis is the existence of deteriorating function in the nigrostriatal pathway with advancing age. The present study was undertaken with ["F]G-fluoro-tdopa and positron emission tomography to determine in vivo the effects of age on the nigrostriatal pathway in a series of 10 asymptomatic subjects (age range, 22-80 years; mean, 49.8 years). A graphical approach was used in the analysis of multiple-time tracer-uptake data to establish the presence of a compartment with unidirectional uptake and to calculate the rate constant, K, for uptake of {'8F)Gfluoro-L-dopa from blood to striatum during steady-state, an index of the functional integrity of nigrostriatal nerve endings. There was a significant linear relationship between K and age (r = 0.80, p < 0.005) with a decrease of 53.3% over the age range studied. These results demonstrate the application of a unidirectional transfer model to the analysis of [L8F]6-fluoro-~-dopa and positron emission tomography data and provide in vivo confirmation of an agerelated impairment of nigrostriatal function.