Experimental Study Of Learning And Memorial Impairment After Seizures In Temporal Lobe Epilepsy Model Established With Stereotactic Technique In Rats

Objective: (1) To explore the method of establishing the temporal lobe epilepsy model in SD rats with stereotactic technique, and to study the EEG's characteristic, the appearance of MR and pathological changes after epileptic seizures. (2)To observe the impairment of learning and memory after seizures in temporal lobe epilepsy in rats, and to explore the correlation between learning and memory impairment and pathological changes of hippocampus? and the changes of intracellular free Ca²⁺ concentration in hippocampus at different tested time. Methods: Sixty SD rats were divided randomly into six groups with 10 rats in each group (control group, normal saline group, 2 weeks group, 1 month group, 2 months group, 3 months group after temporal lobe epilepsy induced by Kainic acid). 2 weeks, 1 month, 2 months, 3 months groups were injected Kainic acid into right hippocampus to induce temporal lobe epilepsy by stereotactic technique, and normal saline group was injected normal saline in right hippocampus. The behavior and EEG changes by deep electrode of the rats were observed. Using 3.0 T MR to observe the appearance of MRI and MRS in hippocampus. The extent of learning and memory impairment was evaluated by Morris water maze. After that, the rats were killed to observe pathologic changes of hippocampus and cortex. Intracellular free Ca²⁺ concentration in hippocampal neurons was measured by using fluorescent Ca²⁺ indicator Fluo-3/AM and laser scanning confocal microscope (LSCM). Results: In control group and normal saline group, rats had neither temporal lobe epilepsy, nor learning and memory impairment, while all the...