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Komlosi, G.

Publications and source records attributed to Komlosi, G..

2 recordsLinked to original sources

Persistently increased post-stress activity of paraventricular thalamic neurons is essential for the emergence of stress-induced maladaptive behavior

ABSTRACTTraumatic events can immediately lead to debilitating symptoms collectively called Acute Stress Disorder (ASD), however the mechanisms of ASD are poorly understood. Using a rodent model of ASD here we identify a crucial communication bottleneck between the brainstem and the forebrain, the calretinin-positive neurons in the paraventricular thalamus (PVT/CR+), that controls ASD. We show that following a single acute stress event, the pre-sleep behavior of the mice is altered for several days in parallel with a persistent increase in the firing rate of PVT/CR+ cells. Optogenetic inhibition of PVT/CR+ neuronal activity after the stress event for one hour was sufficient to rescue both the ASD symptoms and the prolonged increase in PVT/CR+ firing rate. Inhibition applied 5 days later was still able to ameliorate some of the symptoms. These data suggest that post-stress activity of PVT/CR+ neurons play a critical role in mediating the acute forms of stress-related affective dysfunctions. One-Sentence SummaryPost-stress inhibition of paraventricular thalamic neurons prevents the emergence of acute stressed phenotype.

neuroscience↗

Linear summation of metabotropic postsynaptic potentials follows coactivation of neurogliaform interneurons

Summation of ionotropic receptor-mediated responses is critical in neuronal computation by shaping input-output characteristics of neurons. However, arithmetics of summation for metabotropic signals are not known. We characterized the combined ionotropic and metabotropic output of neocortical neurogliaform cells (NGFCs) using electrophysiological and anatomical methods. These experiments revealed that GABA receptors are activated up to 1.8 microns from release sites and confirmed coactivation of putative NGFCs in superficial cortical layers in vivo. Triple recordings from presynaptic NGFCs converging to a postsynaptic neuron revealed sublinear summation of ionotropic GABAA responses and linear summation of metabotropic GABAB responses. Based on a model combining distances of volume transmission from release sites and distributions of all NGFC axon terminals, we postulate that 2 to 3 NGFCs provide input to a point in the neuropil. We suggest that interactions of metabotropic GABAergic responses remain linear even if most superficial layer interneurons specialized to recruit GABAB receptors are simultaneously active.

neuroscience↗