Yonago Acta medica 2003;46:9–6
An Immunohistochemical Study of Perivascular Plaque in Alzheimer’s Disease and Cerebral Amyloid Angiopathy
Chun Hui Yang, Makoto Otsuka and Eisaku Ohama
Department of Neuropathology, Institute of Neurological Sciences, Tottori University Faculty of Medicine, Yonago 683-8504 Japan
Immunohistochemical study of perivascular plaques (PPs) in 7 patients with Alzheimer’s disease (AD) and 4 with cerebral amyloid angiopathy (CAA)(CAA with dementia in 3 patients and CAA with massive cerebral hemorrhage in 1 patient) demonstrated that PPs were also a common form of amyloid β (Aβ) deposits, like SPs and CAAs, in both AD and CAA, and that they had similar immunostaining characteristics to mature senile plaques (SPs), manifesting as always positive for both Aβ42 and Aβ40 but predominant for Aβ42. In addition, PPs were always associated with AT8-positive degenerated neurites and GFAP-positive astrocytes and fibers. These findings suggest that PPs as mature plaques contribute to the development of dementia, especially in CAA with dementia which lack AD pathology. Moreover, semiquantitative analysis revealed no correlation between the number of PPs and that of SPs, but a good correlation between the number of PPs and that of CAAs, suggesting that there was a close relationship of the formation of PPs and the development of CAAs. PPs were also found around non-CAA arteries, although they were frequent around varying degrees of CAAs, suggesting that the initial Aβ42 deposits in PPs contribute to the development of CAAs.
Key words: Alzheimer's disease; cerebral amyloid angiopathy; immunohistochemistry; perivascular plaque; senile plaque
