Previous Article | Next Article ![]()
Infect. Immun., 12 1996, 5053-5060, Vol 64, No. 12
J Fujii, Y Kinoshita, T Kita, A Higure, T Takeda, N Tanaka and S Yoshida
When rabbits were given intravenously purified verotoxin 2 (VT2) at 5
microg/kg of body weight, they developed hemorrhagic diarrhea, flaccid
paresis, an ataxic gait, an opisthotonic posture, and convulsions. To
examine the effects of VT2 toxemia on the rabbit central nervous system,
magnetic resonance imaging and ultrastructural studies were performed. At
24, 57, and 80 h after injection of VT2 into 12 rabbits, T2-weighted images
of the central nervous system were obtained. The initial lesion was noted
at 24 h in the hypothalamic areas of all experimental animals. At 57 h, the
T2 value increased in the medulla of the cerebral hemisphere or the
hippocampus, with a brain stem lesion in six rabbits (50%). The rabbits
with the brain stem lesions, in which neurological signs were very severe,
died within 6 days. Lesions in the cerebellar hemisphere and/or vermis were
noted in four rabbits (33%) that survived more than 1 month. To better
understand the pathogenesis of VT2 in these brain lesions, we examined the
deterioration of the blood-brain barrier and cerebrospinal fluid-brain
barrier by using horseradish peroxidase as a tracer. The tracer was
detected by electron microscopy both in the subendothelial layer, including
the basal lamina, and throughout the cytoplasm of the ependymal cell layer
covering the ventricle after intravenous or intrathecal treatment with
horseradish peroxidase. We also determined the localization of VT2 by
immunoelectron microscopy and found that it was localized on edematous
endothelial cells of capillaries, ependymal cells, and myelin sheaths. The
present study suggests that VT2 was conveyed from the endothelial and
ependymal cell layers and caused edematous changes in the rabbit brain.
Copyright © 1996, American Society for Microbiology
Magnetic resonance imaging and histopathological study of brain lesions in rabbits given intravenous verotoxin 2
Department of Microbiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan. jfujii@med.uoeh-u.ac.jp
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|