Short‐term depression of gap junctional coupling in reticular thalamic neurons of absence epileptic rats

Gap junctional electrical coupling between neurons of the reticular thalamic nucleus (RTN) is critical for hypersynchrony in the thalamo‐cortical network. This study investigates the role of electrical coupling in pathological rhythmogenesis in RTN neurons in a rat model of absence epilepsy. Rhythmic activation resulted in a Ca2+‐dependent short‐term depression (STD) of electrical coupling between pairs of RTN neurons in epileptic rats, but not in RTN of a non‐epileptic control strain. Pharmacological blockade of gap junctions in RTN in vivo induced a depression of seizure activity. The STD of electrical coupling represents a mechanism of Ca2+ homeostasis in RTN aimed to counteract excessive synchronization.

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