mGluR-mediated calcium signalling in the thalamic reticular nucleus

The thalamic reticular nucleus (TRN) plays a major foie in modulating the transfer of information from the thalamus to the cortex. GABAergic inhibition via the TRN is differentially regulated by metabotropic glutamate receptors (mGluRs) and the effect of mGluRs on the membrane potential, on ion channels, and on the plasticity of electrical coupling of TRN neurons has been studied previously. Although mGluRs are generally known to trigger Ca2+ transients, mGluR-mediated Ca2+-transients in TRN neurons have not yet been investigated. In this study, we show that mGluRs can trigger Ca2+-transients in TRN neurons, that these transients depend on intracellular Ca2+-stores, and are mediated by IP3 receptors. Ca2+ transients caused by the group I mGluR agonist DHPG elicit a current that is sensitive to flufenamic acid and has a reversal potential around-40 mV. Our results add mGluR-mediated Ca2+-signalling in the TRN to the state-dependent modulators of the thalamocortical system. (C) 2016 Elsevier Ltd. All rights reserved.