Selective effect of Apo e4 on CA3 and dentate in normal aging and Alzheimer's disease using high resolution MRI at 4 T.
BACKGROUND
Details of the internal hippocampal structure visible at 4 T allow for in vivo volumetry of subfields. The aims of this study were: 1. To determine if Apo e4 has subfield specific effects in controls. 2. To study the influence of Apo e4 on hippocampal subfields in AD.


METHODS
81 subjects (66 controls, mean age 60.8+/-13.6, range: 28-85 years), and 15 AD (mean age 67.5+/-9.3) were studied. Entorhinal cortex, subiculum, CA1, CA1-CA2 transition zone, CA3-4 and dentate gyrus (CA3&DG) and total hippocampal volume were determined using a manual marking strategy.


RESULTS
Significant effects for Apo e4 on the CA3&DG were found in the total control population (p=0.042) and in older controls (61-85 years) (p=0.036) but not in younger (28-60 years) controls. Significant effects for Apo e4 (p=0.0035) on CA3&DG were also found in a subgroup of older subjects and AD subjects. AD with Apo e4 had smaller CA3&DG than AD without Apo e4 (p=0.027).


CONCLUSIONS
These findings suggest that Apo e4 exerts a regionally selective effect on CA3&DG in normal aging and AD.
Center for Imaging of Neurodegenerative Diseases, Department of Veterans Affairs Medical Center, San Francisco, CA 94121, USA. susanne.mueller@ucsf.edu
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SG
Mueller
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Schuff
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Raptentsetsang
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Elman
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MW
Weiner
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics* / Q000473:pathology*; D000544:Alzheimer Disease / Q000235:genetics* / Q000473:pathology*; D053327:Apolipoprotein E4 / Q000235:genetics*; D018891:Dentate Gyrus / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged
D053327:Apolipoprotein E4