In vivo imaging of muscarinic receptors in the aging female brain with (R,R) [I-123]-I-QNB and single photon emission tomography

TY - JOUR

T1 - In vivo imaging of muscarinic receptors in the aging female brain with (R,R) [I-123]-I-QNB and single photon emission tomography

AU - Norbury, R

AU - Travis, M J

AU - Erlandsson, K

AU - Waddington, W

AU - Owens, J

AU - Pimlott, S

AU - Ell, P J

AU - Murphy, D G M

PY - 2005/3

Y1 - 2005/3

N2 - The effect of age on brain muscarinic receptor density is unclear. Some in vivo neuroimaging studies have reported a large age-related reduction in muscarinic receptor density; however, others have reported increases or no change. The variability in these results most likely arises because of the heterogeneity of the populations studied, differences in quantification methods employed, and a paucity of subtype selective ligands. Thus, we used the m(1)/m(4) selective probe (R,R)[I-123]-I-QNB to investigate age-related differences in brain muscarinic receptors in healthy females. We included 10 younger subjects (age range 26-37) and 22 older women (age range 57-82 years). The older women had significantly lower (R,R)[I-123]-T-QNB binding in widespread brain regions including cerebral cortex and hippocampus. Across all subjects, regional binding was significantly negatively correlated with age. Thus, in this population of healthy women, there was an age-related reduction in muscarinic receptor density. This may contribute to age-related differences in cognitive function and risk for Alzheimer's disease. (c) 2004 Elsevier Inc. All rights reserved

AB - The effect of age on brain muscarinic receptor density is unclear. Some in vivo neuroimaging studies have reported a large age-related reduction in muscarinic receptor density; however, others have reported increases or no change. The variability in these results most likely arises because of the heterogeneity of the populations studied, differences in quantification methods employed, and a paucity of subtype selective ligands. Thus, we used the m(1)/m(4) selective probe (R,R)[I-123]-I-QNB to investigate age-related differences in brain muscarinic receptors in healthy females. We included 10 younger subjects (age range 26-37) and 22 older women (age range 57-82 years). The older women had significantly lower (R,R)[I-123]-T-QNB binding in widespread brain regions including cerebral cortex and hippocampus. Across all subjects, regional binding was significantly negatively correlated with age. Thus, in this population of healthy women, there was an age-related reduction in muscarinic receptor density. This may contribute to age-related differences in cognitive function and risk for Alzheimer's disease. (c) 2004 Elsevier Inc. All rights reserved

U2 - 10.1016/j.exger.2004.10.002

DO - 10.1016/j.exger.2004.10.002

M3 - Article

VL - 40

SP - 137

EP - 145

JO - Experimental Gerontology

JF - Experimental Gerontology

IS - 3

ER -