Spike transmission failures in axons from cortical neurons in vivo

iScience, Journal Year: 2024, Volume and Issue: 27(10), P. 110884 - 110884

Published: Sept. 5, 2024

The propagation of action potentials along axons is traditionally considered reliable due to the high safety factor for axonal spike transmission. However, numerical simulations suggest that high-frequency spikes could fail invade distal branches. To explore this experimentally

Language: Английский

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Variability of axon initial segment geometry and its impact on hippocampal pyramidal cell function

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 17, 2024

ABSTRACT Action potentials, the primary information units of nervous system, are usually generated at axon initial segment (AIS). Changes in length and position AIS associated with alterations neuronal excitability but there is only limited about baseline structural variability AIS. This work provides a comprehensive atlas diversity proximal cell geometries across all anatomical axes murine hippocampus, encompassing dorsal-ventral, superficial-deep, proximal-distal regions. We analyzed morphology 3,936 hippocampal pyramidal neurons 12 animals both sexes, focusing on length, position, their association cellular features such as soma dendritic geometries. Notably, axon-carrying dendrites were significantly more common ventral compared to dorsal areas, suggesting functional adaptation regional demands. Validation this finding human samples confirms translational relevance our model. employed NEURON simulations assess implications variability. Here, variation geometry minimally contributed homeostasis, instead increased heterogeneity response patterns neurons.

Language: Английский

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Biocytin-Labeling in Whole-Cell Recording: Electrophysiological and Morphological Properties of Pyramidal Neurons in CYLD-Deficient Mice

Molecules, Journal Year: 2023, Volume and Issue: 28(10), P. 4092 - 4092

Published: May 15, 2023

Biocytin, a chemical compound that is an amide formed from the vitamin biotin and amino acid L-lysine, has been used as histological dye to stain nerve cells. Electrophysiological activity morphology are two key characteristics of neurons, but revealing both electrophysiological morphological properties same neuron challenging. This article introduces detailed easy-to-operate procedure for single-cell labeling in combination with whole-cell patch-clamp recording. Using recording electrode filled biocytin-containing internal solution, we demonstrate pyramidal (PNs), medial spiny (MSNs) parvalbumin neurons (PVs) brain slices, where individual cell elucidated. We first introduce protocol various coupled intracellular diffusion biocytin delivered by glass capillary electrode, followed post hoc reveal architecture biocytin-labeled neurons. An analysis action potentials (APs) neuronal morphology, including dendritic length, number intersections, spine density were performed using ClampFit Fiji Image (ImageJ), respectively. Next, take advantage techniques introduced above, uncovered defects APs spines PNs primary motor cortex (M1) deubiquitinase cylindromatosis (CYLD) knock-out (Cyld-/-) mice. In summary, this provides methodology well single will have many applications neurobiology.

Language: Английский

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Unveiling the cell biology of hippocampal neurons with dendritic axon origin

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Sept. 14, 2023

Summary In mammalian axon-carrying-dendrite (AcD) neurons, the axon emanates from a basal dendrite, instead of soma, to create privileged route for action potential generation at initial segment (AIS). However, it is unclear how such unusual morphology established and whether structure function AIS in AcD neurons preserved. Here, we show that follow an intrinsically encoded developmental program where single precursor neurite first gives rise then AcD. The possesses similar cytoskeletal architecture as canonical stems similarly functions trafficking barrier retain axon-specific molecular composition. unlike soma-derived AIS, does not undergo homeostatic-plasticity, contains less cisternal organelles receives fewer inhibitory inputs. These distinct features could account higher intrinsic excitability neurons. Highlights development driven depend on specific connectivity patterns generate same stem dendrite neuron displays axon-like microtubule organization Similar emerging can selectively filter dendritic cargo chronic homeostatic plasticity inputs

Language: Английский

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Dialectics of perisomatic inhibition—The unity and conflict of opposites

Frontiers in Neural Circuits, Journal Year: 2024, Volume and Issue: 18

Published: Oct. 29, 2024

Over the past three decades, a great deal of attention has been paid to study perisomatic inhibition and inhibitory basket cells. A growing body experimental evidence points leading role cells in generation oscillatory activity various frequency ranges. Recently link between complex behavior demonstrated several laboratories. However, all this is true only for one type interneuron-parvalbumin-positive Nevertheless, where parvalbumin-positive are found, there another cell, cholecystokinin-positive interneurons. These two types interneurons share number common features: they innervate same compartments target neurons often receive excitation from sources, but also differ each other synchrony their GABA release expression receptors. The functional not so obvious. They were thought be involved theta oscillations, however recent measurements free moving animals have put some doubts on hypothesis. Therefore, an important question is, whether these work synergistically or perform opposing actions networks? In mini-review, we attempt answer by putting forward idea that functionally united as entities network, necessary maintain rhythmogenesis "healthy", physiological range.

Language: Английский

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