Reuniens thalamus recruits recurrent excitation in medial prefrontal cortex.

Unlabelled: Medial prefrontal cortex (mPFC) and hippocampus are critical for memory retrieval, decision making and emotional regulation. While ventral CA1 (vCA1) shows direct and reciprocal connections with mPFC, dorsal CA1 (dCA1) forms indirect pathways to mPFC, notably via the thalamic Reuniens nucleus (Re). Neuroanatomical tracing has documented structural connectivity of this indirect pathway through Re however, its functional operation is largely unexplored.

Parvalbumin interneuron-derived tissue-type plasminogen activator shapes perineuronal net structure.

Background: Perineuronal nets (PNNs) are specialized extracellular matrix structures mainly found around fast-spiking parvalbumin (FS-PV) interneurons. In the adult, their degradation alters FS-PV-driven functions, such as brain plasticity and memory, and altered PNN structures have been found in neurodevelopmental and central nervous system disorders such as Alzheimer's disease, leading to interest in identifying targets able to modify or participate in PNN metabolism. The serine protease tissue-type plasminogen activator (tPA) plays multifaceted roles in brain pathophysiology.

Precise spatiotemporal control of voltage-gated sodium channels by photocaged saxitoxin.

Here we report the pharmacologic blockade of voltage-gated sodium ion channels (Nas) by a synthetic saxitoxin derivative affixed to a photocleavable protecting group. We demonstrate that a functionalized saxitoxin (STX-eac) enables exquisite spatiotemporal control of Nas to interrupt action potentials in dissociated neurons and nerve fiber bundles. The photo-uncaged inhibitor (STX-ea) is a nanomolar potent, reversible binder of Nas.

Regulation of Perineuronal Nets in the Adult Cortex by the Activity of the Cortical Network.

Perineuronal net (PNN) accumulation around parvalbumin-expressing (PV) inhibitory interneurons marks the closure of critical periods of high plasticity, whereas PNN removal reinstates juvenile plasticity in the adult cortex. Using targeted chemogenetic approaches in the adult mouse visual cortex, we found that transient inhibition of PV interneurons, through metabotropic or ionotropic chemogenetic tools, induced PNN regression. EEG recordings indicated that inhibition of PV interneurons did not elicit unbalanced network excitation.

Single Cell Multiplex Reverse Transcription Polymerase Chain Reaction After Patch-clamp.

The cerebral cortex is composed of numerous cell types exhibiting various morphological, physiological, and molecular features. This diversity hampers easy identification and characterization of these cell types, prerequisites to study their specific functions. This article describes the multiplex single cell reverse transcription polymerase chain reaction (RT-PCR) protocol, which allows, after patch-clamp recording in slices, to detect simultaneously the expression of tens of genes in a single cell.

Depdc5 knockdown causes mTOR-dependent motor hyperactivity in zebrafish.

Objective: was identified as a major genetic cause of focal epilepsy with deleterious mutations found in a wide range of inherited forms of focal epilepsy, associated with malformation of cortical development in certain cases. Identification of frameshift, truncation, and deletion mutations implicates haploinsufficiency of in the etiology of focal epilepsy. DEPDC5 is a component of the GATOR1 complex, acting as a negative regulator of mTOR signaling.