Effects of cerebral ischemia on the susceptibility to seizure and immunoreacitivity of GFAP in rats

The rat model was established by a modified intraluminal thread method of occlusion and reperfusion in right middle cerebral artery and followed by chronically induced seizure with sub dosage of Pentylenetetrazol(PTZ, 35mg/kg,i.p.). Behaviors were recorded in rat model to evaluate the changes in susceptibility to seizure, then the changes in neuropathology and immunoreactivity of GFAP in sub regions of rat brain were studied by Thionine staining and immunocytochemistry. The results demonstrated that, loss of pyramidal cells of CA 1 and CA 3 occurred on right side of dorsal hippocampus as well as neurons in frontal cortex( P 0.05). Meanwhile, GFAP immunoreacitive astrocytes showed bigger cell bodies, thicker and deeper protrusions and deeper staining( P 0.05). It was suggested that the enhancement in susceptibility to seizure in rats with cerebral ischemia was closely related to the sclerosis of hippocampus, loss of neurons in frontal cortex and proliferation of astrocytes.