Modeling of a controllable acute regional cerebral ischemia in rats and evaluation with CT perfusion imaging and histopathology
- VernacularTitle:可控性大鼠急性脑局部缺血模型的建立及CT灌注成像与病理学评价
- Author:
Chenyang LIANG
;
Peiyi GAO
;
Fang YUAN
;
Lixin XU
;
- Publication Type:Journal Article
- Keywords:
Disease models, animal;
Cerebral ischemia;
Tomography, X ray computed;
Rats, Wistar
- From:
Chinese Journal of Radiology
2001;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To establish a stable and controllable model of acute regional cerebral ischemia in rats, and to evaluate it by CT perfusion imaging and histological study. Methods Twenty eight male Wistar rats were randomly divided into 4 groups, and there were 7 rats in each group. The sham operation rats were defined as the first group, rats suffered from cerebral ischemia for 15 minutes were classified as the second group, rats suffered from cerebral ischemia for 30 minutes and then reperfusion for 1 hour as the third group, and rats suffered from hypo perfusion for 6 hours as the fourth group. Cerebral ischemia or hypo perfusion were induced by inserting a nylon thread of different diameter into right middle cerebral artery (MCA) of rats under the monitoring of regional cerebral blood flow (rCBF) by the Laser Doppler Blood Perfusion Monitor (BPM). rCBF was also examined by dynamic CT perfusion imaging. At the end of the observation time, rats were decapitated, and three rats of each group were performed 2,3,5 triphenyltetrazolium chloride (TTC) staining and four rats were performed histological study. Results In the second group, rCBF was controlled within 5% to 22% under the monitoring by BMP and CT perfusion imaging showed the decreased rCBF in 7 rats, but TTC staining showed red appearance indicating no infarction focus formed. Electronic microscopic study revealed astrocytic swelling and a few of neuronal degeneration. In the third group, rCBF was controlled within 4% to 23% under the monitoring by BMP. There were more severe astrocytic swelling and a lot of neuronal degeneration. The abnormal areas in CT perfusion images were the same as TTC staining. In the fourth group, in accordance with less decrease ment of rCBF (from 38% to 55%) in 7 rats, there were obvious astrocytic swelling and subtle neuronal degeneration. TTC stain did not show ischemia area. All these abnormal changes were not observed in the sham operation rats. Conclusion The controllable acute regional cerebral ischemic model in rats is very stable and repeatable. It can be simulated into the ischemic state of different perfusion level. This model is suitable for the research of acute cerebral infarction and regional cerebral ischemia. The facts that parallel changes existed among BMP measurement, CT perfusion imaging, and brain histology indicated that CT perfusion imaging is accurate and sensitive in evaluating acute regional ischemia.