RESEARCH ARTICLE
Unidirectional Influx and Net Accumulation of PIB
Gunnar Blomquist*, 1, Henry Engler2, Agneta Nordberg3, 4, Anna Ringheim5, Anders Wall5, Anton Forsberg3, Sergio Estrada5, Pernilla Frändberg5, Gunnar Antoni5, Bengt Långström5, 6
Article Information
Identifiers and Pagination:
Year: 2008Volume: 2
First Page: 114
Last Page: 125
Publisher ID: TONIJ-2-114
DOI: 10.2174/1874440000802010114
PMID: 19526073
PMCID: PMC2695622
Article History:
Received Date: 7/7/2008Revision Received Date: 25/8/2008
Acceptance Date: 17/9/2008
Electronic publication date: 13/11/2008
Collection year: 2008

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Abstract
The compound {N-methyl-[11C]}2-(4’-methylaminophenyl)-6-hydroxybenzothiazole, “PIB”, measured by positron emission tomography, has been demonstrated to image brain β-amyloid deposition in Alzheimer’s disease (AD). In the present study the benefit of measuring the PIB accumulation rate together with the unidirectional influx of PIB into the brain was investigated in healthy control subjects and patients with AD. In a monkey changes in the influx rate constant K1 of PIB closely followed changes in CBF, caused by alteration of PaCO2. In addition, K1 was high both in the monkey and in humans, suggesting that this parameter reflects CBF. Most AD patients studied showed clearly higher accumulation rate for PIB than the controls in cortical brain areas, while a few patients showed as low accumulation as the controls. K1 did not correlate with the accumulation rate, indicating that K1 for PIB provides extra information besides the accumulation rate.