Experimental study on the pathogenesis of cerebral infarction in rabbits by injecting sephades G-75 (Part 2): Mechanism of hemorrhagic infarction

Haemorrhagic infarction was studied in rabbits brain with stroke model. In this study, to clarify the mechanism of hemorrhagic infarction, following experiments were used to make stroke models. They were divided into 3 groups : 20 of them were treated by clipping left common carotid artery (group A); 20 of them were not down (group A); and the rest were used a control (group C). All groups were subjected to injection into left internal carotid artery. 0.06 ml of sephadex (SG-75) suspension was used for group A and group B, whereas normal saline solution was used for group C. The histological lesions of rabbits brain were examined with light and electron microscope. Furthermore, carbon mixture was perfused to investigate the dynamic capillary circulation. (1) Haemorrhagic infarction easily developed in the left cerebral cortex as well as in the basic ganglia; (2) In group A, it was more frequently seen than in group B; (3) perfused carbon particles could be seen in capillary bed of group C. However, they could not be seen in the occlusive lesions of A and B groups injected with SG-75. Yet, it was remarkably observed in haemorrhagic infarction area; (4) The blood vessels surrounding the haemorrhagic infarction showed marked degeneration by light and electron microscopy. These results show that the mechanism of haemorrhagic infarction may be due to bleeding from collateral circulation.