Armelle Rancillac

Armelle Rancillac
Collège de France · Center for Interdisciplinary Research in Biology, CNRS/UMR 7241 - INSERM U1050

PhD

About

54
Publications
10,319
Reads
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1,551
Citations
Introduction
I earned my PhD in Neuroscience in 2003 at Paris VI, while working on synaptic plasticity. Then, at the ESPCI, as a postdoctoral fellow, I studied the neurovascular coupling. In 2006, I got a researcher position at the Inserm and studied the role of metabolism on neuronal activity and blood vessel tonus within the VLPO, the structure triggering NREM sleep. In 2014, I got my HDR. Currently, at the Collège de France, I characterize the role of neuroglial interactions in sleep regulation.
Additional affiliations
October 2006 - present
French Institute of Health and Medical Research
Position
  • CR
December 2003 - October 2006
French National Centre for Scientific Research
Position
  • PostDoc Position
July 1999 - November 2003
Sorbonne Université
Position
  • Thèse

Publications

Publications (54)
Poster
Full-text available
Sleep is one of the most universal and essential biological process of life. However, sleep disorders still affect up to one-third of the population and are associated with a wide range of deleterious health consequences including an increased risk of hypertension, diabetes, obesity, depression and stroke. A better understanding of the neurobiologi...
Article
Full-text available
Sleep has been hypothesised to maintain a close relationship with metabolism. Here we focus on the brain structure that triggers slow-wave sleep, the ventrolateral preoptic nucleus (VLPO), to explore the cellular and molecular signalling pathways recruited by an increase in glucose concentration. We used infrared videomicroscopy on ex vivo brain sl...
Article
Full-text available
The tight coupling between increased neuronal activity and local cerebral blood flow, known as functional hyperemia, is essential for normal brain function. However, its cellular and molecular mechanisms remain poorly understood. In the cerebellum, functional hyperemia depends almost exclusively on nitric oxide (NO). Here, we investigated the role...
Article
Full-text available
Study Objectives The regulation of sleep-wake cycles is crucial for the brain’s health and cognitive skills. Among the various substances known to control behavioral states, intraventricular injection of neuropeptide S (NPS) has already been shown to promote wakefulness. However, the NPS signaling pathway remains elusive. In this study, we characte...
Preprint
Although great efforts to characterize the embryonic phase of brain microvascular system development have been made, its postnatal maturation has barely been described. Here, we compared the molecular and functional properties of brain vascular cells on postnatal day (P)5 vs. P15, via a transcriptomic analysis of purified mouse cortical microvessel...
Article
Objectif Le sommeil est un processus biologique essentiel à la vie. Parmi les structures cérébrales régulant les états de vigilance, le noyau préoptique ventrolatéral (VLPO) joue un rôle clef dans la régulation du sommeil lent. Par ailleurs, il a récemment été montré que le BDNF régule l’homéostasie du sommeil lent et que par l’activation de son ré...
Article
Full-text available
Absence of the astrocyte-specific membrane protein MLC1 is responsible for megalencephalic leukoencephalopathy with subcortical cysts (MLC), a rare type of leukodystrophy characterized by early-onset macrocephaly and progressive white matter vacuolation that lead to ataxia, spasticity, and cognitive decline. During postnatal development (from P5 to...
Preprint
Full-text available
The brain dense vascular network is essential for distributing oxygen and nutrients to neural cells. The network develops during embryogenesis and leads to the formation of the endothelial blood-brain barrier (BBB). This barrier is surrounded by mural cells (pericytes and vascular smooth muscle cells (VSMCs)) and fibroblasts. Here, we compared the...
Preprint
Full-text available
Absence of the astrocyte-specific membrane protein MLC1 is responsible for megalencephalic leukoencephalopathy with subcortical cysts (MLC); this rare type of leukodystrophy is characterized by early-onset macrocephaly and progressive white matter vacuolation that lead to ataxia, spasticity, and cognitive decline. During postnatal development (from...
Article
Full-text available
Astrocytes play important roles in brain function via dynamic structural and functional interactions with neurons. Yet the underlying mechanisms remain poorly defined. A typical feature of astrocytes is the high expression of connexins, which mediate their extensive intercellular communication and regulate their structural properties. In particular...
Article
Objectif Les neurones régulateurs du sommeil lent (SL) se situent dans le noyau préoptique ventrolatéral (VLPO). Bien que le sommeil soit un processus essentiel à la vie, les mécanismes moléculaires et cellulaires mis en jeu pendant le SL dans le VLPO restent largement méconnus. Récemment, il a été montré dans le cortex, que les astrocytes particip...
Article
Full-text available
The median preoptic nucleus (MnPO) and the ventrolateral preoptic nucleus (VLPO) are two brain structures that contain neurons essential for promoting non-rapid eye movement (NREM) sleep. However, their connections are still largely unknown. Here, we describe for the first time a slice preparation with an oblique coronal slicing angle at 70° from t...
Preprint
The tight coupling between neuronal activity and the local increase of blood flow termed neurovascular coupling is essential for normal brain function. This mechanism of regulation is compromised in Alzheimer's Disease (AD). In order to determine whether a purely vascular dysfunction or a neuronal alteration of blood vessels diameter control could...
Article
Full-text available
Objectif La régulation des cycles veille-sommeil repose sur des mécanismes complexes et essentiels à la physiologie cérébrale. Parmi les molécules impliquées dans le contrôle des états de vigilance, le neuropeptide S (NPS), un neuropeptide de 20 acides aminés, jouerait un rôle clef. Toutefois, les mécanismes d’action du NPS restent largement méconn...
Article
Full-text available
The characterization of neuronal properties is a necessary first step toward understanding how the ventrolateral preoptic nucleus (VLPO) neuronal network regulates slow-wave sleep (SWS). Indeed, the electrophysiological heterogeneity of VLPO neurons suggests the existence of subtypes that could differently contribute in SWS induction and maintenanc...
Article
Full-text available
We report on wide-field imaging of pulsatile microvascular blood flow in the exposed cerebral cortex of a mouse by holographic interferometry. We recorded interferograms of laser light backscattered by the tissue, beating against an off-axis reference beam with a 50 kHz framerate camera. Videos of local Doppler contrasts were rendered numerically b...
Article
Full-text available
Unlabelled: Sleep-active neurons located in the ventrolateral preoptic nucleus (VLPO) play a crucial role in the induction and maintenance of slow-wave sleep (SWS). However, the cellular and molecular mechanisms responsible for their activation at sleep onset remain poorly understood. Here, we test the hypothesis that a rise in extracellular gluco...
Article
Full-text available
We report on local superficial blood flow monitoring in biological tissue from laser Doppler holographic imaging. In time-averaging recording conditions, holography acts as a narrowband bandpass filter, which, combined with a frequency-shifted reference beam, permits frequency-selective imaging in the radio frequency range. These Doppler images are...
Article
Full-text available
Painful experiences are multilayered, composed of sensory, affective, cognitive and behavioral facets. Whereas it is well accepted that the development of chronic pain is due to maladaptive neuronal changes, the underlying molecular mechanisms, their relationship to the different pain modalities, and indeed the localization of these changes are sti...
Data
The tight coupling between neuronal activity and the local increase of blood flow termed neurovascular coupling is essential for normal brain function. This mechanism of regulation is compromised in Alzheimer’s Disease (AD). In order to determine whether a purely vascular dysfunction or a neuronal alteration of blood vessels diameter control could...
Article
Full-text available
GABAergic interneurons are local integrators of cortical activity that have been reported to be involved in the control of cerebral blood flow (CBF) through their ability to produce vasoactive molecules and their rich innervation of neighboring blood vessels. They form a highly diverse population among which the serotonin 5-hydroxytryptamine 3A rec...
Article
Full-text available
The tight coupling between neuronal activity and the local increase of blood flow termed neurovascular coupling is essential for normal brain function. This mechanism of regulation is compromised in Alzheimer's Disease (AD). In order to determine whether a purely vascular dysfunction or a neuronal alteration of blood vessels diameter control could...
Article
Full-text available
In the neocortex, neuronal Nitric Oxide-Synthase (nNOS) is essentially expressed in two sets of GABAergic neurons: type I neurons displaying a high expression and type II neurons displaying a weaker expression. Using immunocytochemistry on mice expressing GFP under the control of the glutamic acid decarboxylase 67k (GAD67) promoter we studied the d...
Article
Full-text available
Although it is know since more than a century that neuronal activity is coupled to blood supply regulation, the underlying pathways remains to be identified. In the brain, neuronal activation triggers a local increase of cerebral blood flow (CBF) that is controlled by the neurogliovascular unit composed of terminals of neurons, astrocytes, and bloo...
Article
Full-text available
To identify neocortical neurons expressing the type 3 serotonergic receptor, here we used transgenic mice expressing the enhanced green fluorescent protein (GFP) under the control of the 5-HT(3A) promoter (5-HT(3A):GFP mice). By means of whole-cell patch-clamp recordings, biocytin labeling, and single-cell reversed-transcriptase polymerase chain re...
Article
We report new results in angiographic mapping of microvessels in vivo with a wide field optical detection scheme, enabling blood flow contrast measurements in minimally invasive conditions without exogenous marker.
Article
Full-text available
The introduction of a reporter gene into bacterial artificial chromosome (BAC) constructs allows a rapid identification of the cell type expressing the gene of interest. Here we used BAC transgenic mice expressing a tau-sapphire green fluorescent protein (GFP) under the transcriptional control of the neuropeptide Y (NPY) genomic sequence to charact...
Article
Full-text available
An interferometric method for parallel optical spectroscopy in the kilohertz range is reported, as well as its experimental validation in the context of high-speed laser Doppler imaging in vivo. The interferometric approach enables imaging in the low light conditions of a 2 kHz frame rate recording with a complementary metal-oxide semiconductor cam...
Article
Full-text available
We report the assessment of cerebral blood flow (CBF) changes with a wide-field laser Doppler imager based on a CCD camera detection scheme, in vivo, in mice. The setup enables the acquisition of data in minimally invasive conditions. In contrast with conventional laser Doppler velocimeters and imagers, the Doppler signature of moving scatterers is...
Article
Full-text available
We present a new instrument, based on a low-frame-rate (8 Hz) CCD camera used in a heterodyne optical-mixing configuration, that can create wide-field laser Doppler maps. As an illustration, we show results obtained in a mouse brain, in vivo, showing the Doppler signature of blood flow. The instrument is based on a frequency-shifting digital hologr...
Article
Full-text available
Nitric oxide is an important biological messenger that particularly induces the relaxation of smooth muscle cells surrounding vessels, and, hence, controls the flow of blood. This mechanism is essential for brain function, and its fine control, termed functional hyperemia, is supposed to be realized by certain neurons that may release bursts of NO*...
Article
Full-text available
In the cerebellum, dendritic inhibition of Purkinje cells (PCs) is mediated by stellate cells (SCs). These inhibitory interneurons are critically involved in the cerebellar network; they control the timing and firing frequency of PCs, the only output cells of the cerebellar cortex. However, the underlying properties of parallel fiber (PF) to SC exc...
Article
Full-text available
The role of interneurons in neurovascular coupling was investigated by patch-clamp recordings in acute rat cortical slices, followed by single-cell reverse transcriptase-multiplex PCR (RT-mPCR) and confocal observation of biocytin-filled neurons, laminin-stained microvessels, and immunodetection of their afferents by vasoactive subcortical choliner...
Article
Full-text available
Activation of CB1 cannabinoid receptors in the cerebellum acutely depresses excitatory synaptic transmission at parallel fibre-Purkinje cell synapses by decreasing the probability of glutamate release. This depression involves the activation of presynaptic 4-aminopyridine-sensitive K(+) channels by CB1 receptors, which in turn inhibits presynaptic...
Article
Full-text available
Various forms of synaptic plasticity underlying motor learning have already been well characterized at cerebellar parallel fibre (PF)-Purkinje cell (PC) synapses. Inhibitory interneurones play an important role in controlling the excitability and synchronization of PCs. We have therefore tested the possibility that excitatory synapses between PFs a...
Article
Full-text available
A longstanding but still controversial hypothesis is that long-term depression (LTD) of parallel fiber-Purkinje cell synapses in the cerebellum embodies part of the neuronal information storage required for associative motor learning. Transgenic mice in which LTD is blocked by Purkinje cell-specific inhibition of protein kinase C (PKC) (L7-PKCI mut...

Projects

Projects (3)
Project
This project aims to obtain a better understanding of mechanisms of sleep alterations following a traumatic event.