The Largest Group of Superficial Neocortical GABAergic Interneurons Expresses Ionotropic Serotonin Receptors

Lee, Soo Hyun; Hjerling-Leffler, Jens; Zagha, Edward; Fishell, Gord; Rudy, Bernardo

doi:10.1523/jneurosci.1869-10.2010

Cited by 518 publications

(802 citation statements)

References 82 publications

Supporting

Mentioning

736

Contrasting

Unclassified

Order By: Relevance

“…1). As SST and VIP are believed to be mutually exclusive interneuron markers in mouse cortex (1,17) and derive from the medial and caudal ganglionic eminence progenitor populations, respectively (47)(48)(49)(50)(51)(52), this demonstrates that interneurons from distinct progenitor pools are affected by the Dlx1 mutation.…”

Section: Discussionmentioning

confidence: 94%

Chronic reduction in inhibition reduces receptive field size in mouse auditory cortex

Seybold

Stanco

Cho³

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Inhibitory interneurons regulate the responses of cortical circuits. In auditory cortical areas, inhibition from these neurons narrows spectral tuning and shapes response dynamics. Acute disruptions of inhibition expand spectral receptive fields. However, the effects of long-term perturbations of inhibitory circuitry on auditory cortical responses are unknown. We ablated ∼30% of dendrite-targeting cortical inhibitory interneurons after the critical period by studying mice with a conditional deletion of Dlx1. Following the loss of interneurons, baseline firing rates rose and tone-evoked responses became less sparse in auditory cortex. However, contrary to acute blockades of inhibition, the sizes of spectral receptive fields were reduced, demonstrating both higher thresholds and narrower bandwidths. Furthermore, long-latency responses at the edge of the receptive field were absent. On the basis of changes in response dynamics, the mechanism for the reduction in receptive field size appears to be a compensatory loss of corticocortically (CC) driven responses. Our findings suggest chronic conditions that feature changes in inhibitory circuitry are not likely to be well modeled by acute network manipulations, and compensation may be a critical component of chronic neuronal conditions. P rocessing of auditory information in the auditory cortex underlies the conscious perception of sound and speech comprehension. Inhibitory interneurons, representing ∼20% of cortical neurons (1), regulate this processing by shaping the spectral tuning (2-13), temporal tuning (14-16), and response dynamics of local excitatory neurons (5-11). Inhibitory interneurons form multiple subtypes on the basis of morphology, physiology, and biochemistry (1, 17) that likely serve distinct roles in cortical processing.Loss of inhibitory interneurons is observed in conditions that affect cortical processing in humans, and in animal models of human disorders, including aging (18, 19), autism (20), schizophrenia (21-23), traumatic brain injury (TBI) (24), hearing loss (25-28), and tinnitus (29). Often, a particular disease is associated with a specific deficit in a subset of interneurons. For example, rodent models of autism demonstrate a loss of parvalbumin positive (PV + ) interneurons (20), whereas aging and TBI models show a greater loss of somatostatin (SST) + interneurons than other interneuron populations (19,24). The disruption of specific interneuron populations may underlie the particular cognitive defects associated with each condition. Therefore, it is necessary to understand the effects following chronic reductions of particular interneuron subtypes.One mouse model of an adult-onset loss of dendrite-targeting interneurons (DTIs) is the Dlx1 mutant (30). Dlx1 encodes a homeobox transcription factor from the Dlx family that regulates the development, migration, and survival of cortical interneurons (30-32). In Dlx1 mutants, the other Dlx family members compensate for the deficiency and thereby allow interneurons to migrate into cortex (30)....

show abstract

Section: Discussionmentioning

confidence: 94%

Chronic reduction in inhibition reduces receptive field size in mouse auditory cortex

Seybold

Stanco

Cho³

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…This may be due to differences in RS and FS neuron identification in higher mammals (Constantinople et al, 2009;Soares et al, 2017;Vigneswaran et al, 2011). In mice, >90% of FS neurons are PV inhibitory neurons, and >90% of RS neurons are excitatory neurons (Lee et al, 2010;Pfeffer et al, 2013;Rudy et al, 2011), enabling clearer interpretation of roles of cell types. Our findings have two important differences from primate studies.…”

Section: Discussionmentioning

confidence: 99%

Cortical states control visual spatial perception

Speed

Rosario

Burgess

et al. 2018

Preprint

View full text Add to dashboard Cite

SummaryMany factors modulate the state of cortical activity, but the importance of cortical states for sensory perception remains debated.We trained mice to detect spatially localized visual stimuli, and simultaneously measured local field potentials and excitatory and inhibitory neuron populations across layers of primary visual cortex (V1). Cortical states with low firing rates and correlations between excitatory neurons, and reduced oscillatory activity in Layer 4, accurately predicted single trials of visual spatial detection behavior. Our results show that cortical states exert strong effects at the initial stage of cortical processing in V1, and play a decisive role for visual spatial behavior in mice.

show abstract

“…Coverage was extremely low in L1, L2, lower L6A, and L6B. The PV-, SOM-, and CR-negative INs may be immunoreactive for ionotropic serotonin receptors, which have recently been shown to be expressed in virtually all SOM-and PV-negative INs in mouse neocortex (57).…”

Section: Molecular Markers Of Ins In a Corticalmentioning

confidence: 93%

Inhibitory interneurons in a cortical column form hot zones of inhibition in layers 2 and 5A

Meyer

Schwarz

Wimmer

et al. 2011

Proc. Natl. Acad. Sci. U.S.A.

204

164

View full text Add to dashboard Cite

Although physiological data on microcircuits involving a few inhibitory neurons in the mammalian cerebral cortex are available, data on the quantitative relation between inhibition and excitation in cortical circuits involving thousands of neurons are largely missing. Because the distribution of neurons is very inhomogeneous in the cerebral cortex, it is critical to map all neurons in a given volume rather than to rely on sparse sampling methods. Here, we report the comprehensive mapping of interneurons (INs) in cortical columns of rat somatosensory cortex, immunolabeled for neuron-specific nuclear protein and glutamate decarboxylase. We found that a column contains ∼2,200 INs (11.5% of ∼19,000 neurons), almost a factor of 2 less than previously estimated. The density of GABAergic neurons was inhomogeneous between layers, with peaks in the upper third of L2/3 and in L5A. IN density therefore defines a distinct layer 2 in the sensory neocortex. In addition, immunohistochemical markers of IN subtypes were layer-specific. The "hot zones" of inhibition in L2 and L5A match the reported low stimulus-evoked spiking rates of excitatory neurons in these layers, suggesting that these inhibitory hot zones substantially suppress activity in the neocortex.F or a quantitative understanding of the interaction between excitatory and inhibitory synaptic transmission in the neocortex, it is crucial to obtain data on the absolute numbers and the relative distribution of excitatory and inhibitory (mostly GABAergic) neurons [interneurons (INs)] in a cortical column. Only on the basis of such prevalence numbers is it possible to interpret data on single-cell physiology (1-8) and synaptic connections of pairs of neurons (9-12) at the circuit level. The distribution of cortical neurons and INs has therefore been the objective of several studies over the past decades (13-15). Statistical sampling methods were used because mapping tens of thousands of neurons was not feasible. Although the nominal error bounds of such methods are in the range of 10-20%, the reported absolute numbers differed strongly among studies, especially for sparse neuron populations, such as INs and their subtypes. The ratio of INs reported for the somatosensory cortex varied between 15% and 25%, thus by almost a factor of 2 (13,16,17). Data on possible differences in IN density between layers in a cortical column were contradictory (13,15,16,18,19).To resolve these substantial discrepancies, we undertook the complete mapping of INs in entire cortical columns using the cytoarchitectonic barrels in L4 as a reference frame for the thalamocortical innervation volume (20) in postnatal day (P) 25-36 rat vibrissal cortex. Our data show that the overall prevalence of inhibitory neurons was previously overestimated by almost a factor of 2. We find a unique substructure of the distribution of INs in a cortical column that can explain the layer-specific differences in the excitability in neocortex. The distribution of INs defines layer 2 as a distinct neocortical layer.

show abstract

The Largest Group of Superficial Neocortical GABAergic Interneurons Expresses Ionotropic Serotonin Receptors

Cited by 518 publications

References 82 publications

Chronic reduction in inhibition reduces receptive field size in mouse auditory cortex

Chronic reduction in inhibition reduces receptive field size in mouse auditory cortex

Cortical states control visual spatial perception

Inhibitory interneurons in a cortical column form hot zones of inhibition in layers 2 and 5A

Contact Info

Product

Resources

About