Imaging of nicotinic and muscarinic receptors in Alzheimer's disease:Effect of tacrine treatment
A. Nordberg
Bok Engelsk 1997
| Utgitt | 1997
|
|---|---|
| Omfang | Side 78- 84
|
| Opplysninger | Functional imaging techniques offer new possibilities for furtherunderstanding of changes in functional correlates of structural andbiological changes in dementia disorders like Alzheimer's disease(AD). Regional disturbances in glucose metabolism and cerebral bloodflow are known to occur in AD brains and probably roughly correlateto changes in neurotransmitter activities. A proper estimate would beto visualize the neuroreceptors themselves. In this study thecholinergic nicotinic and muscarinic receptors were studied in brainby positron emission tomography (PET). The rate constant k(2)* (s) (-)C-11-nicotine was significantly higher (+43%) in temporal cortex ofAD patients compared to controls (p < 0.017) indicating a lowerbinding of C-11-nicotine in AD brains compared to controls. Treatmentwith the cholinesterase inhibitor tacrine (80 mg daily) during 3months to AD patients resulted in a mean plasma concentration of 7.7+/- 0.8 ng/ml and a corresponding inhibition of the cholinesteraseactivity in plasma by 34 +/- 5%. A significantly lower k(2)*(increased binding) for C-11-nicotine binding (-15%; p < 0.006) wasobtained in the temporal cortex after 3 months of treatment comparedto prior treatment. The muscarinic antagonist C-11-benztropine wasused to visualize muscarinic receptors and the binding capacity of C-11-benztropine (K-R) was found to be decreased in the temporal cortexafter 3 months of tacrine treatment.
|
| Emner |
