Role of the thalamic reticular nucleus in the generation of rhythmic thalamo-cortical activities subserving spike and waves
The role of the reticular thalamic nucleus (RTN) in pacing rhythmic cortical activities subserving spike-waves (SW) discharges has been investigated in rats.
Intracellular recordings from thalamic slices in vitro demonstrated that RTN neurons from control animals possess a set of Ca2+/K+ membrane conductances which enable them to produce rhythmic oscillatory activities.
In vivo, studies of Ca2+-conductance blockade by intrathalamic injections of Cd2+ were performed on 24 callosotomized Wistar rats displaying spontaneous SW discharges, bred at the Centre de Neurochimie, Strasbourg. A significant decrement in ipsilateral SW activity was consistently observed in all RTN-injected animals 40 min after Cd2+ injection. By contrast, animals which received Cd2+ injection into the ventroposterior complex (VP) showed only small changes in ipsilateral SW. It is concluded that Ca2+-dependent oscillatory properties of the RTN are critical for the expression of genetically determined SW discharges in the Wistar model.
KeywordsCurrent Pulse Intracellular Recording Generalize Epilepsy Reticular Thalamic Nucleus Neuron Injection Cannulae
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