1991 Volume 9 Issue 2 Pages 161-168
Bipolar stainless steel electrodes were stereotaxically implanted into the right dorsal hippocampus (CAl) and stainless steel screws were anchored epidurally to both sides of the frontal bone of 9 male Wistar rats. Hippocampal Kindling was completed through daily electrical stimulation at afterdischarge thresholds. The fully kindled rats were exposed to immobilization stress using wire netting for 30 minutes 30 minutes after intraperitoneal injection of 5.5mg/kg of bemegride. Bemegride induced repetitive clonic seizures involving the head, forelimbs and trunk showing cortical rhythmic epileptic discharges lasting a few seconds. Behavioral observation and EEG recordings from the cortex and hippocampus were carried out for 30 minutes before the start of immobilization, for 30 minutes during immobilization, and for 50minutes after release from immobilization.
Immobilization stress significantly decreased the frequencies of the epileptec seizures and cortical rhythmic epileptic discharges and significantly reduced the duration of the cortical rhythmic discharges in comparison with those during the preceeding non-immobilized period. Frequencies of the epileptic seizures and cortical rhythmic discharges further decreased immediately after release from immobilization, and then increased again. Conversely, frequency of sporadic spikes from the dorsal hippocampus was significantly increased during immobilization stress, and showed transient decrease immediately after release from immobilization followed by increase.
