Cerebral ischemia in rabbit: a new experimental model with immunohistochemical investigation

Regional cerebral ischemia was produced in the rabbit by unilateral transorbital occlusion of the middle cerebral artery (procedure I); the middle cerebral and azygos anterior cerebral or anterior communicating artery (procedure II); or the middle cerebral, azygos anterior cerebral or anterior communicating, and internal carotid artery (procedure III). Evolution of ischemic lesions was examined with the immunohistochemical reaction for tubulin. With procedure I, ischemic lesions did not become constantly visible for 6 h in the basal ganglia and for 8 h in the frontoparietal region of the cerebral cortex. With procedure II, it was shortened to 3 h in the basal ganglia and to 6 h in the cerebral cortex. With procedure III, the ischemic lesions were observed in 1 h both in the basal ganglia and in the cerebral cortex as loss of the reaction for tubulin in the neuropil, nerve cell bodies, and dendrites. The evidence of neuronal damage became apparent in the same areas later by staining with hematoxylin-eosin. The experimental model presented here may be suitable for investigation of the mechanism that shifts reversible ischemia to cerebral infarction and for evaluation of the effectiveness of pharmacological intervention.