Brain Advance Access published online on May 11, 2009
Brain, doi:10.1093/brain/awp069
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Increased binding to 5-HT1A and 5-HT2A receptors is associated with large vessel infarction and relative preservation of cognition
1 King's College London, Wolfson Centre for Age-Related Diseases, London, UK 2 Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, UK 3 NIHR Biomedical Research Centre for Mental Health, The South London and Maudsley NHS Foundation Trust & The Institute of Psychiatry, King's College London, London, UK
Correspondence to:
Clive G. Ballard, King's College London, Wolfson Centre for Age-Related Diseases, Guy's Campus, London Bridge, London SE1 1UL, UK E-mail: clive.ballard{at}kcl.ac.uk
Vascular dementia accounts for 
15–20% of all dementias. In addition, a significant subset of people with Alzheimer's disease have concurrent cerebrovascular disease. Vascular dementia is caused by different cerebrovascular morphological abnormalities including large artery territory infarction (multi-infarct vascular dementia) and sub-cortical ischaemic vascular dementia. Despite this distinction, there is a lack of studies examining the neurochemistry of individual vascular dementia subtypes. Serotonin is believed to play an important role in cognition, and serotonin receptors may provide a novel target for future anti-dementia therapeutics. This study aimed to determine levels of two serotonin receptors in subtypes of vascular dementia and relate any changes to cognition. We have determined, using saturation radioligand binding, the binding parameters (affinity and maximal binding) of (3H)-WAY 100635 binding to 5-HT1A receptors and (3H)-ketanserin binding to 5-HT2A receptors in post-mortem tissue from the frontal and temporal cortices of patients with either multi-infarct vascular dementia, sub-cortical ischaemic vascular dementia, mixed Alzheimer's disease/vascular dementia or stroke no dementia (SND). 5-HT1A and 5-HT2A receptor binding was significantly increased in the temporal cortex of patients with either multi-infarct vascular dementia or SND, compared to age-matched controls. 5-HT1A receptor maximal binding in the temporal cortex was also positively correlated with cognition as determined by Mini-Mental State Examination (MMSE) and Cambridge Assessment of Mental Health for the Elderly scores (CAMCOG). These results reveal an important distinction between the neurochemistry of multi-infarct vascular dementia/SND and sub-cortical ischaemic vascular dementia, suggesting that pharmacological manipulation of serotonin offers the possibility to develop novel therapies for stroke and multi-infarct vascular dementia patients. The results also highlight the importance of the cortical 5-HT1A receptor in mediating cognition.
Key Words: vascular dementia; stroke; serotonin; cognition
Abbreviations: CERAD, Consortium to Establish a Registry for Alzheimer's disease; MIVaD, multi-infarct dementia; MMSE, Mini-Mental State Examination; SIVaD, sub-cortical ischaemic vascular dementia; SND, stroke no dementia; 5-HT, 5-hydroxytryptamine
Received October 30, 2008. Revised January 20, 2009. Accepted February 18, 2009.