Histological and immunohistochemical characteristics of cerebral amyloid angiopathy in elderly dogs.
BACKGROUND
Cerebral amyloid angiopathy (CAA) is a disorder characterized by amyloid deposition in the wall of cerebral blood vessels. The deposits of amyloid occur frequently in the blood vessels of the frontal, parietal and occipital cortex.


OBJECTIVE
To examine the characteristics of CAA classified according to the Vonsattel scale in elderly dogs histologically and immunohistochemically as well as the semi-quantitative evaluation of the amyloid deposits in the different segments of the brain.


METHODS
The brains of 36 dogs of different breeds and sexes, which had been routinely necropsied, were used and divided into two groups: dogs from 1 to 5 and 10 to 18 years old. The tissue sections were stained by hematoxylin-eosin, Congo red and immunohistochemically.


RESULTS
Amyloid was accumulated in the wall of cerebral blood vessels in 70% of dogs over the age of 10 years predominantly in the frontal cortex. CAA was demonstrated in elderly dogs as follows: in the frontal cortex (n = 19 or 63%), the parietal cortex (n = 12 or 40%), the hippocampus (40%) and the cerebellum (n = 5 or 17%). The deposits of amyloid in the wall of blood vessels detected by Congo red staining were also Aβ1-14 and Aβ1-42 immunohistochemically positive. Most commonly, the amyloid deposits affected a moderate number of blood vessels. The accumulation of amyloid was immunohistochemically revealed in the blood vessel walls as well as in the senile plaques and neurons.


CONCLUSIONS
The amount of amyloid in the arterial walls increased with age in dogs, whereas the amyloid accumulated in plaques was Congo red negative.
a Department of Veterinary Pathology, Faculty of Veterinary Medicine , University of Belgrade , Belgrade , Serbia.
Slađan
S
Nešić
a Department of Veterinary Pathology, Faculty of Veterinary Medicine , University of Belgrade , Belgrade , Serbia.
Vladimir
V
Kukolj
a Department of Veterinary Pathology, Faculty of Veterinary Medicine , University of Belgrade , Belgrade , Serbia.
Darko
D
Marinković
a Department of Veterinary Pathology, Faculty of Veterinary Medicine , University of Belgrade , Belgrade , Serbia.
Ivana
I
Vučićević
a Department of Veterinary Pathology, Faculty of Veterinary Medicine , University of Belgrade , Belgrade , Serbia.
Milijan
M
Jovanović
D000375:Aging; D000682:Amyloid / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000473:pathology; D016657:Cerebral Amyloid Angiopathy / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D004283:Dog Diseases / Q000209:etiology / Q000473:pathology*; D004285:Dogs; D005260:Female; D008297:Male
D000682:Amyloid
Dog; amyloid; angiopathy; brain; canine