Topic: parvalbumin-positive interneurons

A growing understanding of cortical interneuron circuits has highlighted the role of specific inhibitory interneurons in shaping sensory tuning and discrimination acuity. In auditory cortex, neuron-derived neurotrophic factor-expressing interneurons (NDNF-INs) reside in layer 1 where they receive tonotopic projections from the auditory thalamus. In turn, they inhibit the dendrites of out-of-column excitatory pyramidal neurons while disinhibiting within-column neurons via descending projections to parvalbumin-positive interneurons. This circuitry suggests that NDNF-INs are well-poised to modula

Given the remarkable cognitive and neuropsychiatric impairments linked to cannabis use, most of the anatomical and functional data on the endocannabinoid (ECB) system has been gathered from higher brain regions like the prefrontal cortex, leaving aside structures that integrate the sensory systems. However, considering the conservation of cortical organization across areas and species, studying the latter would not only impact the understanding of the perceptual effects of cannabinoids, but potentially provide insights into the neural circuits involved in more complex behaviours.To this end, w

Nicotinic acetylcholine receptors (nAChRs) are widely expressed throughout the brain and they are involved in the control of fundamental neural functions. One of the most common nAChR subtypes are heteromeric beta2-containing (beta2*) nAChRs. In the prefrontal cortex (PFC), beta2* nAChRs are expressed by different neuronal populations with different effects on behavior. To better understand functional role of beta2* nAChRs, we need to know which neuronal types in the PFC express them and what is the effect of these receptors on behavior. In the present project, we used FISH to map the expressi

Traumatic Brain Injury (TBI) is known to impair motor coordination and affect cognitive functions. Parvalbumin-positive interneurons (PV-INs) are one subpopulation of GABAergic cells, which can balance their inhibitory output on connected pyramidal neurons, thereby influencing cortical network excitability. Here we investigated TBI-induced, morphological and functional changes of PV-Basket Cells (PV-BCs) in the ipsilateral hemisphere of somatosensory cortex and the underlying mechanisms. We used our established TBI model and performed immunohistochemistry, fluorescence in situ hybridization an

Dlx5/6genes encode for two homeobox transcription factors expressed in most forebrain GABAergic neurons, and involved in differentiation of Parvalbumin-positive interneurons (PV). PV interneurons are essential for normal brain function andPV expression is a hallmark of neuronal maturation. Their activity and distribution are altered in psychiatric conditions. Epidemiological studies suggest a link of the Dlx5/6locus with psychiatric disorders such as schizophrenia and autism spectrum disorder.Fluoxetine(FLX) is used to treat depression and anxiety disorders. Its administration induces a juveni

Numerous brain pathologies are characterized by an imbalance between excitatory and inhibitory actions in brain microcircuits. The loss or loss of function of parvalbumin-positive interneurons (PV+), an interneurons subtype, is accompanied by network disturbance and cognitive dysfunction in many neuro-psychiatric diseases. Platelet-activating factor acetylhydrolase 1B subunit alpha (known as Lis1) is a regulator of dynein mediated motility, mitosis nuclear positioning and microtubule organization. Lis1 gene mutation has been associated with lissencephaly in humans and defects in neural migrati

De novo mutations in STXBP1 are among the most prevalent causes of neurodevelopmental disorders, and lead to haploinsufficiency, cortical hyperexcitability, epilepsy and other symptoms in patients. Given that Munc18-1, the protein encoded bySTXBP1, is essential for excitatory and inhibitory synaptic transmission, it is currently not understood why mutations cause hyperexcitability. We discover that overall inhibition in canonical feedforward microcircuits is defective in a P15-22 mouse model for Stxbp1 haploinsufficiency. Unexpectedly, we find that inhibitory synapses formed by parvalbumin-pos

Resting-state fMRI (rsfMRI) is widely used to map brain network organization in healthy and pathological states. However, the neural underpinnings governing brainwide fMRI functional connectivity (interareal activity correlation) remain unclear. Neocortical excitatory/inhibitory (E/I) balance critically affects local and long-range information processing and can conceivably bias fMRI connectivity, as suggested by the widely reported neocortical E/I imbalance and altered fMRI connectivity in multiple brain disorders. Here, we combine chemogenetics, rsfMRI and electrophysiology to causally probe