[A rat middle cerebral artery thrombosis model for evaluation of thrombolytic and antithrombotic agents].

The purpose of this study was to develope a rat model of cerebral artery thrombosis by adding FeCl3 to the surface of right middle cerebral artery (MCA) for 30 min. After 4 h, 8 h, 24 h, 48 h, 72 h, 1 week and 2 week, the extent of neurologic deficits of rats was evaluated and after 24 h and 48 h the size of cerebral infarction was measured. The results indicate that the features of neurologic deficits and infarction were similar to those of the rat focal cerebral ischemia model established by Tamura et al (1981). The nature of thrombus formed in our experiment is combined-thrombus. The antithrombotic effect of aspirin and the thrombolytic effect of urokinase were also examined. Aspirin (50 mg.kg-1) was given by duodenum 30 min before adding FeCl3 to the surface of the right MCA and urokinase (4000 U.kg-1, iv) was given 30 min after thrombosis. After operation, the behavior of rats were observed. The cerebral infarction was evaluated 24 h after thrombosis. The infarcted areas in the aspirin and the urokinase groups were reduced to 20% and 11% those of the control group, respectively. The neurologic deficits were also attenuated. These studies suggest that this rat model may be used for testing not only antithrombotic but also thrombolytic agents.