The Effects of Venous Ischaemia on the Subependymal and Choroid Plexus Morphology in Rat

Abstract

Morphological changes of ependyma, subependyma and choroids plexus regions were evaluated after experimental anastomotic venous occlusion in twenty male Sprague-Dawley rats. In this model, small burr holes were made over the anterior and posterior anastomotic veins and after precisely locating these vessels, bipolar coagulation and microscissors were used to perform permanent occlusion. Three days later, rats were sacrificed by perfusion and fixation and specimens were evaluated by histopathological techniques. Morphological changes of ependymal, subependymal and choroids plexus cells were evaluated in operated and intact hemispheres and revealed cell proliferation in the subventricular zone adjacent to the territory of venous occlusion in the operated hemisphere as well as midline shift, brain oedema, subcortical petechial haemorrhage, brain infarction and hemispheric swelling. In conclusion, following anterior (the vein of Throlard) and posterior (the vein of Labbé) anastomotic vein occlusion, cell proliferation can be seen in the choroids plexus, ependymal and subependymal regions in rats. We conclude that these morphological changes might be part of a self-repairing mechanism in the brain.

Key words

Venous ischaemia - rat brain - ependymal - subependymal - choroid plexus - cell morphology

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