Authors: Safiye Çavdar Hüsniye Hacıoğlu Secan Y Doğukan Filiz Onat
Publish Date: 2011/07/01
Volume: 33, Issue: 2, Pages: 251-259
Abstract
Abnormal functional properties of the thalamocortical connections were reported in the absence of epilepsy The present study compares the ratios of terminals ‘RL’—round vesicles large terminals ‘RS’—round vesicles small terminals and ‘F’—flattened vesicles and synapse in three firstorder ventrobasal lateral geniculate and anteroventral and in three higherorder posterior lateral posterior and mediodorsal thalamic nuclei of genetic absence epilepsy rats from Strasbourg GAERS with our earlier quantitative studies of normal Wistar rats to show whether quantitative differences were present in GAERS as compared to Wistar rat Rats were perfused transcardially the brains were removed and cut as 300 μm coronal sections Parts of the six thalamic nuclei were removed for routine electron microscopy and GABA immunocytochemistry Twenty photographs from each section at 20000× magnification were taken and the terminals were identified as RL RS or F 1 In normal Wistar rats as in cats the proportion of driver terminals RL and synapses is lower in higherorder than in firstorder thalamic nuclei but this difference is not present in GAERS animals 2 The proportions of RS terminals and synapses for each thalamic nucleus showed no significant differences between GAERS and Wistar rats for any of the thalamic nuclei 3 In GAERS the proportion of inhibitory F terminals and synapses was significantly high in the VB and low in the LP thalamic nucleus These abnormal ratios in the GAERS may be the cause of the spikeandwave discharges of absence seizures or may represent a compensatory response of the thalamocortical circuitry to the absence seizuresThis project was supported by Marmara University Scientific Research Council SAGCYLP0708080194 We confirm that we read the journals position on issues involved in ethical publication and affirm that this report is consistent with those guidelines
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