Age-related decline in nicotinic receptor availability with [123I]5-IA-85380 SPECT

Yale University School of Medicine, New Haven, CT 06510, USA.
Neurobiology of aging (Impact Factor: 5.01). 02/2008; 30(9):1490-7. DOI: 10.1016/j.neurobiolaging.2007.12.008
Source: PubMed


Human postmortem studies have reported decreases with age in high affinity nicotine binding in brain. We investigated the effect of age on beta(2)-containing nicotinic acetylcholine receptor (beta(2)-nAChR) availability in eight brain regions of living human subjects using the ligand [(123)I]5-IA-85380 ([(123)I]5-IA) and single photon emission computed tomography (SPECT). Healthy, nonsmokers (N=47) ranging in age from 18 to 85 were administered [(123)I]5-IA using a bolus plus constant infusion paradigm and imaged 6-8h later under equilibrium conditions. The effect of age on regional beta(2)-nAChR availability (V(T), regional brain activity/free plasma parent, a measure proportional to the binding potential) was analyzed using linear regression and Pearson's correlation (r). Age and regional beta(2)-nAChR availability were inversely correlated in seven of the eight brain regions analyzed, with decline ranging from 32% (thalamus) to 18% (occipital cortex) over the adult lifespan, or up to 5% per decade. These results in living human subjects corroborate postmortem reports of decline in high affinity nicotine binding with age and may aid in elucidating the role of beta(2)-nAChRs in cognitive aging.

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    10/2015; 1(2). DOI:10.3389/fmolb.2015.00059
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    • "(ρ = 0.56, p < 0.05) but not contralateral putamen (ρ = 0.49, p = 0.07) (Mitsis et al., 2009a "
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    • "Considering the decrease of a4b2 - nAChRs during normal and pathologic aging ( Gotti et al . , 2006 ; Mitsis et al . , 2009 ; Picciotto and Zoli , 2002 ) , we can hypothesize that the selective involvement of mPFC a4b2 * - nAChRs by S 38232 would produce cholinergic transients and enhance attentional processes which in turn , would restore WM performance along with preventing the age - related increase of CREB phosphorylation in the PL . Moreover , considerin"
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