| Budget Amount *help |
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1995: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1994: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
|---|
| Research Abstract |
Cerebral amyloid angiopathy (CAA) in the elderly, designated by the deposition of beta protein, has been thought as a cause of cerebral hemorrhage. We have reported that CAA is the most common cause of superficial cerebral hemorrhage in patients older than 60 years. However, the mechanism for the rupture of amyloid-laden vessels remains unclear. We have revealed that CAA seen in some sporadic aged individuals can show a immunohistochemical reactivity towards antibodies to both beta protein and cystatin C (Cys C), and that Cys C was not actually an integral component of cerebrovascular amyloid fibrils in these cases. Immunohistochemical studies were carried out on biopsy specimens from 29 patients with cerebral subcortical hemorrhage using primary antibodies against beta protein, Cys C,and apolipoprotein E (Apo E). Cerebral vessels in all cases were reactive for anti-beta protein and Apo E antibodies, and in 26 (89.7%) out of 29 cases showed positive immunoreactivity for Cys C.beta Protein and Apo E immunoreactivities were demonstrated predominantly in the media and adventitia of a small artery. Serial sections immunostained for Cys C showed an intense labelling of the adventitia of vessel wall. On electron microscopy, amyloid fibrils, measuring 10 nm in width, were located mainly in the tunica media of the arteries, and in less involved vessels they tended to be situated among the collagen fibers in the adventitia and smooth muscle cells in the outer zone of the media. On immunoelectron microscopy for beta protein, all of the amyloid fibrils in the vascular walls were specifically labelled by gold particles. The present study indicates that Cys C superimposed beta protein amyloid in CAA plays an important role for the rupture of amyloid-laden vessels.
|
