We investigated the effects of muscimol on generation of spike-wave discharges (SWDs) and shortterm plasticity alterations in the somatosensory cortex of WAG/Rij rats. The rats were implanted with a twisted tripolar electrode into the somatosensory cortex and with an intraventricular cannula into the right cerebral ventricle. EEG recordings were made before and after muscimol and saline injections. Paired-pulse stimulations (200 μsec, 100-1000 μA, 0.1 sec–1) were applied to the somatosensory cortex at 50-, 100-, 400-, and 500-msec-long intervals for 50 min. Pharmacological amplification of GABAergic transmission in the somatosensory cortex exerted an inhibitory effect on the thalamo-cortical circuit underlying the generation of spike-wave discharges (SWDs). Ten minutes post-injection of muscimol, paired-pulse facilitation was significantly reduced at 50- and 100-msec-long interpulse intervals (P < 0.05). The data obtained suggest that muscimol suppresses generation of SWDs and changes short-term plasticity via imitation of the effects of GABA in inhibitory synapses.
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Nejad, G.G., Vastyanov, R.S., Shahabi, P. et al. Abnormalities in the GABAergic Inhibitory System Leading to the Development of Spike-Wave Discharges in the Somatosensory Cortex of Wag/Rij Rats. Neurophysiology 47, 454–458 (2015). https://doi.org/10.1007/s11062-016-9555-0
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DOI: https://doi.org/10.1007/s11062-016-9555-0