Measurement of the α4β2 nicotinic receptor in vivo in Alzheimer's disease with 123I–5IA–85380 SPECT

O'Brien, J. T., Colloby, S. J., Pakrasi, S., Perry, E. K., Pimlott, S. L. and Wyper, D. J. (2006) Measurement of the α4β2 nicotinic receptor in vivo in Alzheimer's disease with 123I–5IA–85380 SPECT. Alzheimer's Association 10th International Conference on Alzheimer's Disease and Related Disorders, Madrid, Spain, 15-20 Jul 2006. S677. (doi: 10.1016/j.jalz.2006.05.2264)

Abstract

Background Loss of the α4β2 nicotinic receptor subtype is found at autopsy in Alzheimer's disease. We investigated in vivo changes in this receptor using SPECT with 123I–5–Iodo–3–[2(S)–2–azetidinylmethoxy] pyridine (5IA–85380), a novel nicotinic acetylcholine receptor ligand which binds predominantly to the α4β2 receptor. Methods 32 subjects (16 Alzheimer's disease (AD) and 16 elderly controls) underwent 123I–5IA–85380 and perfusion (99mTc–HMPAO) SPECT scanning. Region of interest analysis was performed with cerebellar normalization. Results Significant bilateral reductions in nicotinic receptor binding were identified in frontal (left, p=0.004; right, p=0.002), striatal (left, p=0.004; right, p=0.003) in right medial temporal (p=0.04) and pons (p<0.001) in AD compared to controls. There were no significant correlations with clinical and cognitive measures. The pattern of nicotinic binding significantly differed from that of perfusion in both AD subjects and controls. Conclusion Using 123I–5IA–85380 SPECT we found changes consistent with significant reductions in the nicotinic α4β2 receptor in cortical and striatal brain regions, independent of perfusion. This method could facilitate diagnosis and may be useful for monitoring disease progression and response to treatment in AD and related diseases.

• Item Type: Conference or Workshop Item
• Additional Information: Abstract - available in Alzheimer's and Dementia: The Journal of the Alzheimer's Association 2(3S_Part_22): S677.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Pimlott, Dr Sally and Wyper, Professor David
• Authors: O'Brien, J. T., Colloby, S. J., Pakrasi, S., Perry, E. K., Pimlott, S. L., and Wyper, D. J.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing; College of Science and Engineering > School of Physics and Astronomy
• ISSN: 1552-5279