Clinical Analysis Of Operation Curative Effect Of Patients With Intractable Temporal Lobe Epilepsy And The Change Of NMDA Receptor Subunits In Cortex Of Temporal Lobe

Epilepsy, a brain dysfunctional syndrome with many pathogenies, is characterized by recurrent and temporary disorder of brain function. There are about 6,000,000 patients with epilepsy in China, with about 400,000 new epilepsy diagnoses every year. Within this population, about 1,200,000 patients are suffering from medically intractable epilepsy, which not only seriously affected the patients'life quality, but also brought burden and pressure to their families and society.The intractable temporal lobe epilepsy is the largest part of epilepsy that underwent surgical treatment and the percentage is 60-70%. With the development of epileptic surgery, the curative effect of operation of intractable temporal lobe epilepsy was very well. The clinical data showed that the effective power of operation of intractable temporal lobe epilepsy has above 90%.N-methyl-D-aspartate receptor (NMDAR), a subtype of ionotropic receptor for glutamate (N-methyl D-aspartate is a name of its selective specific agonist), could induce slow excitatory effect. Activation of NMDA receptors results in the opening of an ion channel that is highly permeable for Ca2+. The influx of Ca2+ mediates variety of physiological processes, such as synaptic plasticity and synaptic transmission. Although the pathogenic mechanisms of epilepsy are complicated, the relationship of NMDAR and epilepsy is affirmative. It was reported that, NMDAR played an important role in the development and maintenance of epilepsy.Part 1 Clinical analysis of operation curative effect of patients with intractable temporal lobe epilepsyObjective: To explore the curative effect of operations of patients with intractable temporal lobe epilepsy and analyses the effects of complex using techniques for locating epileptic zone on the curative effect of operations.Methods: 20 patients who underwent surgical treatment for intractable temporal lobe epilepsy were chosen in the study. The operations were performed at the Department of Functional Neurosurgery of Hebei General Hospital between January 2008 and February 2009. The techniques of MRI, video electroencephalogram (VEEG) and magnetoecephalogram (MEG) were used for locating epileptic zone of pre-operation. The electrocorticogram (ECoG) was used to locate the epileptic zone exactly during the operation. The curative effect of operation of patients was evaluated by Engel's standard.Results: Single-side cortex of temporal lobe and hippocamp of 20 patients were resected, left-side 8 (40%), right-side 12(60%). None of 20 patients underwent hemorrhage, infection and hemiparalysis after operation. 2 patients underwent nominal aphasia and recovered for 10-14 days after operation. The postoperative follow-up lasted 12 to 24 months (average 16.8 months). Engel'sâ… : 16 patients (80%),â…¡: 3 patients (15%),â…¢: 1 patient (5%). The effective rate was 100% and the curative effect of operation of 95% patients was well. The detection rate of MRI was 55%. The detection rate of focal cortical dysplasia (FCD) was 35% and 77.78% of hippocampal sclerosis were found. During the intermission, the detection rate of epileptiform discharges was 100% and seizures of every patient were recorded by VEEG. The epileptic zones of 8 patients (40%) were located in left-side temporal lobe and hippocamp, 12 patients (60%) were in right. During the intermission, the detection rate of epileptiform discharges was 100% by MEG. 17 patients (85%) were located in single-side cortex of temporal lobe and hippocamp, 3 patients (15%) were in double-side cortex of temporal lobe. No seizure was recorded by MEG. The epileptiform discharges of cortex of temporal lobe and hippocamp which were resected were found by ECoG during the operation.Conclusion: 1. The curative effect of operation of patients with intractable temporal lobe epilepsy was well. 2. By complex using techniques for locating epileptic zone, the curative effect of operation would been improved and the postoperative complications would been decreased.Part 2 The change of NMDA receptor subunits in cortex of temporal lobe of patients with intractable temporal lobe epilepsyObjective: To observed the change of NMDA receptor subunits in cortex of temporal lobe of patients with intractable temporal lobe epilepsy.Methods: The cortical tissue of epilepsy group was obtained from 20 patients who underwent surgical treatment for intractable temporal lobe epilepsy. The cortical tissue of control group was obtained form 10 patients who underwent surgical treatment for vascular malformation of temporal lobe. The material was freshly obtained during operations performed at the Department of Functional Neurosurgery of Hebei General Hospital between January 2008 and February 2009. All cortical tissue was obtained quickly in ice box after resection. The process was bioclean. Neocortical samples of epilepsy group were chosen from the most epileptogenic area as determined by intraoperative electrocortico- graphic recordings. Cortical tissue of control group was obtained far away from the focus of infection. The relative levels of NMDA receptor subunits (NR1, NR2A, and NR2B) in the neocortex which was resected form patients with intractable temporal lobe epilepsy were detected by immunohistochemistry staining and Syber Green-fluorescent quantitation PCR.Results: After HE staining, the slices were observed by light microscope at 40 and 100 magnification. The slices of control group showed clear normal cortical lamination (6 layers), without neuronic abnormalities. In slices resected from patients with temporal lobe epilepsy the histomorphological changes included dyslamination, large, immature, dysmorphic neurons or balloon cells. The pathologic diagnosis of samples of epilepsy group was FCD. Compared with control group, the expression (protein and mRNA) of NMDA receptor subunits (NR1, NR2A, NR2B) in neocortex of epilepsy group was increased significantly (p<0.01).Conclusion: The expression (protein and mRNA) of NMDA receptor subunits (NR1, NR2A, NR2B) in cortex of temporal lobe of patients with temporal lobe epilepsy was increased significantly, which might represent a possible mechanism of intractable epilepsy and FCD induced epilepsy.