Subacute Electrical Stimulation of the Human Hippocampus: IV Hippocampal Benzodiazepine Receptor Binding.
Abstract number :
2.161
Submission category :
Year :
2000
Submission ID :
2614
Source :
www.aesnet.org
Presentation date :
12/2/2000 12:00:00 AM
Published date :
Dec 1, 2000, 06:00 AM
Authors :
Luisa Rocha, Marcos Velasco, Francisco Velasco, Ana Luisa Velasco, Magdalena Briones, Mexican Institute of Psychiatry SS, Mexico City, Mexico; Neurosurgery-Neurophysiology Natl Med Ctr IMSS, Mexico City, Mexico.
RATIONALE: Autoradiographic determination of Benzodiazepine Receptor Binding (BDZRB) is a method to evaluate the activity of the GABA system receptors indicative of neuronal inhibition of a given brain region. METHODS: Here, we determined the BZDRB of the hippocampal cells after the subacute electrical stimulation of the hippocampus (SAHCS) by means of the optical density of the standards of tissue radioactivity values. Hippocampal tissues were obtained from 3 different patient groups: Epileptic hippocampi resected by "en bloc" anterior temporal lobectomies in patients with SAHCS (group 1) and without SAHCS (group 2) and normal hippocampus resected from autopsy of non-epileptic patients who died by an extra-cerebral cause (group 3). RESULTS: If one considers the normal hippocampal BDZRB equals to 100% (group 3), it was found that SAHCS significantly increased the epileptic hippocampal BZDRB from 60 to 80% (group 1) in relation to the BDZRB found in the non-stimulated epileptic hippocampus (5-10%) (group 2). CONCLUSIONS: These data suggest that SAHCS produces its antiepileptic effect, at least in part, due to and inhibitory process mediated by the GABA system. Partially supported by CONACYT Mexico, contracts Nums. 348 A930 and 95 785003.