Objective      To determine the effects of 2 rat models of experimental intracerebral hemorrhage (ICH) (collagenase infusion and autoblood infusion) on neurological outcome

permeability of blood-brain barrier and glial scar hyperplasia.       Methods      A total of 144 male Sprague-Dawley rats were randomly and equally divided into 2 groups

autoblood injection model or collagenase injection model. According to the preset-time (3

7

14 and 21 d after ICH

n=6 for each time point)

several indexes including Bederson scores

Evans blue permeation

brain dry-wet ratio

HE staining and immunohistochemical assay were assessed comprehensively.       Results      Bederson scores

Evans blue permeation and water content of perihematoma revealed that the neurological outcome and blood brain barrier permeability were gradually returned to normal with time elapse in the both models. Compared with the autoblood injection model

bederson scores

Evans blue permeation and water content of perihematoma were obviously increased in the collagenase injection model at the time points of 3

7 and 14 d (P0.05). HE staining results showed that the hematoma absorption

inflammatory exudation

and glial scar formation were enhanced in both models with time elapse. As compared with the collagenase injection model

more hematoma absorption

less inflammatory exudation and less glial scar formation were observed in the brain tissue of the autoblood injection model in 14 and 21 d after injection. Immunohistochemical staining showed that the expression of glial fibrillary acidic protein (GFAP) was increased with time elapse in the perihematoma region of the both models

with the highest levels in the collagenase injection model at 7 and 21 d.       Conclusion      As compared with the autoblood injection model

poorer neurological outcome

worse blood brain barrier breakdown and more glial scar formation are seen in the collagenase injection model. So this model is more suitable for long-term clinical study of cerebral hemorrhage.