Read by QxMD icon Read


Samuel D Gale, Gabe J Murphy
The superficial layers of the superior colliculus (sSC) receive retinal input and project to thalamic regions - the dorsal lateral geniculate (dLGN) and lateral posterior (LP; or pulvinar) nuclei -that convey visual information to cortex. A critical step towards understanding the functional impact of sSC neurons on these parallel thalamo-cortical pathways is determining whether different classes of sSC neurons, which are known to respond to different features of visual stimuli, innervate overlapping or distinct thalamic targets...
June 13, 2018: Journal of Neurophysiology
Danielle L Kopke, Kendal Broadie
FM dyes are used to study the synaptic vesicle (SV) cycle. These amphipathic probes have a hydrophilic head and hydrophobic tail, making them water-soluble with the ability to reversibly enter and exit membrane lipid bilayers. These styryl dyes are relatively non-fluorescent in aqueous medium, but insertion into the outer leaflet of the plasma membrane causes a >40X increase in fluorescence. In neuronal synapses, FM dyes are internalized during SV endocytosis, trafficked both within and between SV pools, and released with SV exocytosis, providing a powerful tool to visualize presynaptic stages of neurotransmission...
May 24, 2018: Journal of Visualized Experiments: JoVE
David H Root, David J Estrin, Marisela Morales
Ventral tegmental area (VTA) neurons play roles in reward and aversion. The VTA has, in addition to dopamine neurons, glutamatergic neurons expressing VGluT2. Here, by determining the firing patterns of VTA-VGluT2 neurons expressing channelrhodopsin 2, we identified a major subpopulation of VTA-VGluT2 neurons whose firing rates decreased or were unchanged during sucrose consumption and increased during facial airpuff presentation. We identified a small subpopulation of VTA-VGluT2 neurons whose firing rates increased in response to both rewarding and aversive stimuli...
April 27, 2018: iScience
Xiaojian Li, Naoki Yamawaki, John M Barrett, Konrad P Körding, Gordon M G Shepherd
Quantitative analysis of corticocortical signaling is needed to understand and model information processing in cerebral networks. However, higher-order pathways, hodologically remote from sensory input, are not amenable to spatiotemporally precise activation by sensory stimuli. Here, we combined parametric channelrhodopsin-2 (ChR2) photostimulation with multi-unit electrophysiology to study corticocortical driving in a parietofrontal pathway from retrosplenial cortex (RSC) to posterior secondary motor cortex (M2) in mice in vivo ...
2018: Frontiers in Systems Neuroscience
Rafael C Almada, Andreas J Genewsky, Daniel E Heinz, Paul M Kaplick, Norberto C Coimbra, Carsten T Wotjak
Defensive behavioral responses are essential for survival in threating situations. The superior colliculus (SC) has been implicated in the generation of defensive behaviors elicited by visual, tactile and auditory stimuli. Furthermore, substantia nigra pars reticulata (SNr) neurons are known to exert a modulatory effect on midbrain tectum neural substrates. However, the functional role of this nigrotectal pathway in threating situations is still poorly understood. Using optogenetics in freely behaving mice, we activated SNr projections at the level of the SC, and assessed consequences on behavioral performance in an open field test (OFT) and the beetle mania task (BMT)...
2018: Frontiers in Neural Circuits
Kiran Yellappa Vajanthri, Parul Yadav, Suruchi Poddar, Sanjeev Kumar Mahto
Optogenetics is a new and emerging field that involves techniques of optics and genetic engineering to influence cellular functionality. In this work, we have successfully incorporated a non-selective cationic channel channelrhodopsin-2 (ChR2) into human hepatocellular carcinoma (HepG2) cells. A plasmid construct AAV-CAG-ChR2-GFP was used for liposomal transfection into the cells. ChR2 is a light sensitive membrane channel that opens upon illumination with blue light. Plasmid DNA isolation from E. coli XL 10 gold bacteria by alkaline lysis method resulted in a DNA concentration of 1150 μg/mL...
June 2018: Tissue & Cell
Nikolas C Vann, Francis D Pham, Kaitlyn E Dorst, Christopher A Del Negro
The brainstem pre-Bötzinger complex (preBötC) generates inspiratory breathing rhythms, but which neurons comprise its rhythmogenic core? Dbx1-derived neurons may play the preeminent role in rhythm generation, an idea well founded at perinatal stages of development but incompletely evaluated in adulthood. We expressed archaerhodopsin or channelrhodopsin in Dbx1 preBötC neurons in intact adult mice to interrogate their function. Prolonged photoinhibition slowed down or stopped breathing, whereas prolonged photostimulation sped up breathing...
May 2018: ENeuro
R L Tom, A Ahuja, H Maniates, C M Freeland, M J F Robinson
Drug and behavioral addictions are characterized by an intense and focused pursuit of a single reward above all others. Pursuit of the addictive reward is often compulsively sought despite adverse consequences and better alternative outcomes. Here we explored the ability of the central amygdala (CeA) to powerfully bias choice, causing specific rewards to be almost compulsively preferred. Rats were trained on an operant choice task in which they could choose to respond on either of two levers to receive a sucrose reward, one of which was paired with optogenetic stimulation of the CeA using channelrhodopsin-2 (ChR2)...
May 23, 2018: European Journal of Neuroscience
Payal A Makadia, Sarah A Najjar, Jami L Saloman, Peter Adelman, Bin Feng, Joseph F Margiotta, Kathryn M Albers, Brian M Davis
Epithelial cells of the colon provide a vital interface between the internal environment (lumen of the colon) and colon parenchyma. To examine epithelial-neuronal signaling at this interface, we analyzed mice in which channelrhodopsin (ChR2) was targeted to either TRPV1-positive afferents or to villin expressing colon epithelial cells. Expression of a ChR2-EYFP fusion protein was directed to either primary sensory neurons or to colon epithelial cells by crossing Ai32 mice with TRPV1-Cre or villin-Cre mice, respectively...
May 22, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Timothy J Hibberd, Jing Feng, Jialie Luo, Pu Yang, Vijay K Samineni, Robert W Gereau, Nigel Kelley, Hongzhen Hu, Nick J Spencer
BACKGROUND & AIMS: Strategies are needed to increase gastrointestinal transit without systemic pharmacologic agents. We investigated whether optogenetics, focal application of light to control enteric nervous system excitability, could be used to evoke propagating contractions and increase colonic transit in mice. METHODS: We generated transgenic mice with Cre-mediated expression of light-sensitive channelrhodopsin-2 (CHR2) in calretinin neurons (CAL-ChR2 Cre+ mice); Cre- littermates served as controls...
May 18, 2018: Gastroenterology
Guela Sokhadze, Peter Whitney Campbell, William Guido
The thalamic reticular nucleus (TRN), a shell-like structure comprised of GABAergic neurons, gates signal transmission between thalamus and cortex. While TRN is innervated by axon collaterals of thalamocortical and corticothalamic neurons, other ascending projections modulate activity during different behavioral states such as attention, arousal, and sleep-wake cycles. One of the largest arise from cholinergic neurons of the basal forebrain and brainstem. Despite its integral role, little is known about how or when cholinergic innervation and synapse formation occurs...
May 14, 2018: European Journal of Neuroscience
S C Barnett, B A L Perry, J C Dalrymple-Alford, L C Parr-Brownlie
Technology allowing genetically targeted cells to be modulated by light has revolutionised neuroscience in the past decade, and given rise to the field of optogenetic stimulation. For this, non-native, light activated proteins (e.g. channelrhodopsin) are expressed in a specific cell phenotype (e.g. glutamatergic neurons) in a subset of central nervous system nuclei, and short pulses of light of a narrow wavelength (e.g. blue, 473 nm) are used to modulate cell activity. Cell activity can be increased or decreased depending on which light activated protein is used...
May 9, 2018: Hippocampus
Stefan Keplinger, Barbara Beiderbeck, Stylianos Michalakis, Martin Biel, Benedikt Grothe, Lars Kunz
The Mongolian gerbil ( Meriones unguiculatus ) is widely used as a model organism for the human auditory system. Its hearing range is very similar to ours and it uses the same mechanisms for sound localization. The auditory circuits underlying these functions have been characterized. However, important mechanistic details are still under debate. To elucidate these issues, precise and reversible optogenetic manipulation of neuronal activity in this complex circuitry is required. However, genetic and genomic resources for the Mongolian gerbil are poorly developed...
2018: Frontiers in Cellular Neuroscience
Soon K Cheong, Wenjun Xiong, Jennifer M Strazzeri, Constance L Cepko, David R Williams, William H Merigan
Adaptive optics retinal imaging of fluorescent calcium indicators is a minimally invasive method used to study retinal physiology over extended periods of time. It has potential for discovering novel retinal circuits, tracking retinal function in animal models of retinal disease, and assessing vision restoration therapy. We previously demonstrated functional adaptive optics imaging of retinal neurons in the living eye using green fluorescent calcium indicators; however, the use of green fluorescent indicators presents challenges that stem from the fact that they are excited by short-wavelength light...
2018: Advances in Experimental Medicine and Biology
Sarah E Mondello, Michael D Sunshine, Amanda E Fischedick, Sam J Dreyer, Gregory D Horwitz, Polina Anikeeva, Philip J Horner, Chet T Moritz
Electrical intraspinal microstimulation (ISMS) at various sites along the cervical spinal cord permits forelimb muscle activation, elicits complex limb movements, and may enhance functional recovery after spinal cord injury (SCI). Here, we explore optogenetic spinal stimulation (OSS) as a less invasive and cell-type specific alternative to ISMS. To map forelimb muscle activation by OSS in rats, adeno-associated viruses (AAV) carrying the blue-light sensitive ion channels channelrhodopsin-2 (ChR2) and Chronos were injected into the cervical spinal cord at different depths and volumes...
May 2, 2018: Journal of Neurophysiology
Thomas Mager, David Lopez de la Morena, Verena Senn, Johannes Schlotte, Anna D Errico, Katrin Feldbauer, Christian Wrobel, Sangyong Jung, Kai Bodensiek, Vladan Rankovic, Lorcan Browne, Antoine Huet, Josephine Jüttner, Phillip G Wood, Johannes J Letzkus, Tobias Moser, Ernst Bamberg
Optogenetics revolutionizes basic research in neuroscience and cell biology and bears potential for medical applications. We develop mutants leading to a unifying concept for the construction of various channelrhodopsins with fast closing kinetics. Due to different absorption maxima these channelrhodopsins allow fast neural photoactivation over the whole range of the visible spectrum. We focus our functional analysis on the fast-switching, red light-activated Chrimson variants, because red light has lower light scattering and marginal phototoxicity in tissues...
May 1, 2018: Nature Communications
Pardo-Peña Kenia, Lorea-Hernández Jonathan Julio, Camacho-Hernández Neira Polet, Ordaz Benito, Villasana-Salazar Benjamín, Morales-Villagrán Alberto, Fernando Peña-Ortega
Hydrogen peroxide (H2 O2 ) is a messenger involved in both damaging neuroinflammatory responses and physiological cell communication. The ventrolateral medulla, which regulates several vital functions including breathing and blood pressure, is highly influenced by hydrogen peroxide, whose extracellular levels could be determined by hypoxia and microglial activity, both of which modulate ventrolateral medulla function. Therefore, in this study we aimed to test whether different patterns of hypoxia and/or putative microglial modulators change extracellular hydrogen peroxide in the ventrolateral medulla by using an enzymatic reactor online sensing procedure specifically designed for this purpose...
April 28, 2018: Brain Research
Jae Hoon Jeong, Ji Suk Chang, Young-Hwan Jo
Release of fatty acids from lipid droplets upon activation of the sympathetic nervous system (SNS) is a key step in nonshivering thermogenesis in brown adipose tissue (BAT). However, intracellular lipolysis appears not to be critical for cold-induced thermogenesis. As activation of the SNS increases glucose uptake, we studied whether intracellular glycolysis plays a role in BAT thermogenesis. To stimulate BAT-innervating sympathetic nerves in vivo, we expressed channelrhodopsin-2 (ChR2) in catecholaminergic fibers by crossbreeding tyrosine hydroxylase-Cre mice with floxed-stop ChR2 mice...
April 27, 2018: Scientific Reports
Jessica Ausborn, Hidehiko Koizumi, William H Barnett, Tibin T John, Ruli Zhang, Yaroslav I Molkov, Jeffrey C Smith, Ilya A Rybak
The circuit organization within the mammalian brainstem respiratory network, specifically within and between the pre-Bötzinger (pre-BötC) and Bötzinger (BötC) complexes, and the roles of these circuits in respiratory pattern generation are continuously debated. We address these issues with a combination of optogenetic experiments and modeling studies. We used transgenic mice expressing channelrhodopsin-2 under the VGAT-promoter to investigate perturbations of respiratory circuit activity by site-specific photostimulation of inhibitory neurons within the pre-BötC or BötC...
April 2018: PLoS Computational Biology
Jae Hoon Jeong, Dong Kun Lee, Shun-Mei Liu, Streamson C Chua, Gary J Schwartz, Young-Hwan Jo
Proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (ARC) respond to numerous hormonal and neural signals, resulting in changes in food intake. Here, we demonstrate that ARC POMC neurons express capsaicin-sensitive transient receptor potential vanilloid 1 receptor (TRPV1)-like receptors. To show expression of TRPV1-like receptors in ARC POMC neurons, we use single-cell reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, electrophysiology, TRPV1 knock-out (KO), and TRPV1-Cre knock-in mice...
April 2018: PLoS Biology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"