A method for predicting the success of Pulsinell's four-vessel occlusion rat model by LDF monitoring of cerebral blood flow decline

Background: Since the electrocoagulation of the bilateral vertebral artery in the Pulsinelli's four-vessel occlusion method must rely on the experimental experience of the researchers, it has no objective quantitative guidance. The high mortality or insufficient brain injury in the animals occur early in the experiment, requiring more animals to account for those not suitable.

New method: In this study, Laser Doppler flowmetry (LDF) was used to monitor the decline in blood flow during electrocoagulation in rats to control the degree of brain injury.

Results: Rats were divided into the sham-operated, mild electrocoagulation, moderate electrocoagulation and severe electrocoagulation groups. In this three electrocoagulation groups, the decline in cerebral blood flow of rats was 26% ± 7%, 44% ± 14% and 69% ± 7% and the corresponding mortality rates were 0%, 33% and 100%, respectively. Rats in the moderate electrocoagulation group, which indicated that the model was successful, had a low mortality rate, showed a high degree of brain injury.

Comparison with existing methods: The position of the vertebral artery cannot be directly visualized and the degree of cerebral ischemia can only be adjudicated by the experimental experience of the researcher, with no objective guideline by observation. We used LDF to monitor the decline in blood flow during and after electrocoagulation, allowing us to effectively control the degree of cerebral ischemia and thus the mortality of animals.

Conclusions: With the addition of LDF monitoring, Pulsinelli's four-vessel occlusion can be used as a stable and reliable model for global cerebral ischemiareperfusion injury.