Atrioventricular valvular angiectasis in Sprague-Dawley rats.
Subendothelial heart valve angiectasis has been reported in cows, dogs, pigs, rats, mice, and in human fetuses and newborns. We observed a high incidence (62 in 208 animals examined) of spontaneous angiectasis on the atrioventricular (AV) valves in 10- to 40-week-old Sprague-Dawley rats. The angiectasis was observed predominately on the septal cusp of the right AV valve and located near the AV ostium in 57 of 62 animals. Of the remaining 5 valvular angiectases, 2 were present on the parietal cusp of the right AV valve and 3 were on the left AV valve. The angiectases were single or multiple, ranging from 40 to 300 microm in diameter and were characterized by light microscopy as blood-filled dilatations lined by endothelium. Spontaneously occurring abnormalities in normal laboratory animals, such as the spontaneous valvular angiectasis reported here, need to be differentiated from drug-related lesions.
Fang
H
H
Department of Pathology, Drug Safety Evaluation, Pharmaceutical Research Institute, Bristol-Myers Squibb Company, Syracuse, NY 13221-4755, USA. hengsheng.fang@bms.com
Howroyd
P C
PC
Fletcher
A M
AM
Diters
R W
RW
Woicke
J
J
Sasseville
V G
VG
Bregman
C L
CL
Freebern
W J
WJ
Durham
S K
SK
Mense
M G
MG
D000818:Animals; D005260:Female; D006349:Heart Valve Diseases / Q000473:pathology / Q000662:veterinary*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012376:Rodent Diseases / Q000473:pathology*; D014652:Vascular Diseases / Q000473:pathology / Q000662:veterinary*