Manipulations of central amygdala neurotensin neurons alter the consumption of ethanol and sweet fluids in mice

AbstractThe central nucleus of the amygdala plays a significant role in alcohol use and other affective disorders; however, the genetically-defined neuronal subtypes and their projections that govern these behaviors are not well known. Here we show that neurotensin neurons in the central nucleus of the amygdala of male mice are activated by in vivo ethanol consumption and that genetic ablation of these neurons decreases ethanol consumption and preference in non-ethanol dependent animals. This ablation did not impact preference for sucrose, saccharin, or quinine. We found that the most robust projection of the central amygdala neurotensin neurons was to the parabrachial nucleus, a brain region known to be important in feeding behaviors, conditioned taste aversion, and alarm. Optogenetic stimulation of projections from these neurons to the parabrachial nucleus is reinforcing, and increases ethanol drinking as well as consumption of sucrose and saccharin solutions. These data suggest that this central amygdala to parabrachial nucleus projection influences the expression of reward-related phenotypes and is a novel circuit promoting consumption of ethanol and palatable fluids.

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Involvement of MCH-oxytocin neural relay within the hypothalamus in murine nursing behavior

Scientific Reports ◽

10.1038/s41598-021-82773-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoko Kato ◽

Harumi Katsumata ◽

Ayumu Inutsuka ◽

Akihiro Yamanaka ◽

Tatsushi Onaka ◽

...

Keyword(s):

Mammalian Species ◽

Virgin Female ◽

Essential Elements ◽

Hypothalamic Nucleus ◽

Male Mice ◽

Hypothalamic Area ◽

Functional Roles ◽

Genetic Ablation ◽

Optogenetic Stimulation ◽

Stimulation Of

AbstractMultiple sequential actions, performed during parental behaviors, are essential elements of reproduction in mammalian species. We showed that neurons expressing melanin concentrating hormone (MCH) in the lateral hypothalamic area (LHA) are more active in rodents of both sexes when exhibiting parental nursing behavior. Genetic ablation of the LHA-MCH neurons impaired maternal nursing. The post-birth survival rate was lower in pups born to female mice with congenitally ablated MCH neurons under control of tet-off system, exhibiting reduced crouching behavior. Virgin female and male mice with ablated MCH neurons were less interested in pups and maternal care. Chemogenetic and optogenetic stimulation of LHA-MCH neurons induced parental nursing in virgin female and male mice. LHA-MCH GABAergic neurons project fibres to the paraventricular hypothalamic nucleus (PVN) neurons. Optogenetic stimulation of PVN induces nursing crouching behavior along with increasing plasma oxytocin levels. The hypothalamic MCH neural relays play important functional roles in parental nursing behavior in female and male mice.

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Opposing Influence of Sensory and Motor Cortical Input on Striatal Circuitry and Choice Behavior

10.1101/446708 ◽

2018 ◽

Author(s):

Christian R. Lee ◽

Alex J. Yonk ◽

Joost Wiskerke ◽

Kenneth G. Paradiso ◽

James M. Tepper ◽

...

Keyword(s):

Ex Vivo ◽

Dorsal Striatum ◽

Behavioral Effect ◽

Projection Neurons ◽

Cortical Input ◽

Optogenetic Stimulation ◽

Main Input ◽

Opposing Effects ◽

Stimulation Of

SummaryThe striatum is the main input nucleus of the basal ganglia and is a key site of sensorimotor integration. While the striatum receives extensive excitatory afferents from the cerebral cortex, the influence of different cortical areas on striatal circuitry and behavior is unknown. Here we find that corticostriatal inputs from whisker-related primary somatosensory (S1) and motor (M1) cortex differentially innervate projection neurons and interneurons in the dorsal striatum, and exert opposing effects on sensory-guided behavior. Optogenetic stimulation of S1-corticostriatal afferents in ex vivo recordings produced larger postsynaptic potentials in striatal parvalbumin (PV)-expressing interneurons than D1- or D2-expressing spiny projection neurons (SPNs), an effect not observed for M1-corticostriatal afferents. Critically, in vivo optogenetic stimulation of S1-corticostriatal afferents produced task-specific behavioral inhibition, which was bidirectionally modulated by striatal PV interneurons. Optogenetic stimulation of M1 afferents produced the opposite behavioral effect. Thus, our results suggest opposing roles for sensory and motor cortex in behavioral choice via distinct influences on striatal circuitry.

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Parylene photonics: a flexible, broadband optical waveguide platform with integrated micromirrors for biointerfaces

Microsystems & Nanoengineering ◽

10.1038/s41378-020-00186-2 ◽

2020 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Jay W. Reddy ◽

Maya Lassiter ◽

Maysamreza Chamanzar

Keyword(s):

Optical Waveguides ◽

Brain Activity ◽

Low Loss ◽

Parylene C ◽

Optogenetic Stimulation ◽

Patterned Illumination ◽

The Brain ◽

532 Nm ◽

Stimulation Of

Abstract Targeted light delivery into biological tissue is needed in applications such as optogenetic stimulation of the brain and in vivo functional or structural imaging of tissue. These applications require very compact, soft, and flexible implants that minimize damage to the tissue. Here, we demonstrate a novel implantable photonic platform based on a high-density, flexible array of ultracompact (30 μm × 5 μm), low-loss (3.2 dB/cm at λ = 680 nm, 4.1 dB/cm at λ = 633 nm, 4.9 dB/cm at λ = 532 nm, 6.1 dB/cm at λ = 450 nm) optical waveguides composed of biocompatible polymers Parylene C and polydimethylsiloxane (PDMS). This photonic platform features unique embedded input/output micromirrors that redirect light from the waveguides perpendicularly to the surface of the array for localized, patterned illumination in tissue. This architecture enables the design of a fully flexible, compact integrated photonic system for applications such as in vivo chronic optogenetic stimulation of brain activity.

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Hypothalamic circuitry underlying stress-induced insomnia and peripheral immunosuppression

Science Advances ◽

10.1126/sciadv.abc2590 ◽

2020 ◽

Vol 6 (37) ◽

pp. eabc2590 ◽

Cited By ~ 1

Author(s):

Shi-Bin Li ◽

Jeremy C. Borniger ◽

Hiroshi Yamaguchi ◽

Julien Hédou ◽

Brice Gaudilliere ◽

...

Keyword(s):

Restraint Stress ◽

Immune Cell ◽

Cell Mass ◽

Neural Substrates ◽

Functional Responses ◽

Genetic Ablation ◽

Optogenetic Stimulation ◽

Response To Stress ◽

Paraventricular Nucleus Of Hypothalamus ◽

Stimulation Of

The neural substrates of insomnia/hyperarousal induced by stress remain unknown. Here, we show that restraint stress leads to hyperarousal associated with strong activation of corticotropin-releasing hormone neurons in the paraventricular nucleus of hypothalamus (CRHPVN) and hypocretin neurons in the lateral hypothalamus (HcrtLH). CRHPVN neurons directly innervate HcrtLH neurons, and optogenetic stimulation of LH-projecting CRHPVN neurons elicits hyperarousal. CRISPR-Cas9–mediated knockdown of the crh gene in CRHPVN neurons abolishes hyperarousal induced by stimulating LH-projecting CRHPVN neurons. Genetic ablation of Hcrt neurons or crh gene knockdown significantly counteracts restraint stress–induced hyperarousal. Single-cell mass cytometry by time of flight (CyTOF) revealed extensive changes to immune cell distribution and functional responses in peripheral blood during hyperarousal upon optogenetic stimulation of CRHPVN neurons simulating stress-induced insomnia. Our findings suggest both central and peripheral systems are synergistically engaged in the response to stress via CRHPVN circuitry.

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0074 Inhibitory Neurons in the Dorsomedial Medulla Promote REM Sleep

SLEEP ◽

10.1093/sleep/zsaa056.072 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A30-A30

Author(s):

J Stucynski ◽

A Schott ◽

J Baik ◽

J Hong ◽

F Weber ◽

...

Keyword(s):

Rem Sleep ◽

Nrem Sleep ◽

Inhibitory Neurons ◽

Brain State ◽

Sleep Regulation ◽

Optogenetic Stimulation ◽

Electrophysiological Recordings ◽

Stimulation Of

Abstract Introduction The neural circuits controlling rapid eye movement (REM) sleep, and in particular the role of the medulla in regulating this brain state, remains an active area of study. Previous electrophysiological recordings in the dorsomedial medulla (DM) and electrical stimulation experiments suggested an important role of this area in the control of REM sleep. However the identity of the involved neurons and their precise role in REM sleep regulation are still unclear. Methods The properties of DM GAD2 neurons in mice were investigated through stereotaxic injection of CRE-dependent viruses in conjunction with implantation of electrodes for electroencephalogram (EEG) and electromyogram (EMG) recordings and optic fibers. Experiments included in vivo calcium imaging (fiber photometry) across sleep and wake states, optogenetic stimulation of cell bodies, chemogenetic excitation and suppression (DREADDs), and connectivity mapping using viral tracing and optogenetics. Results Imaging the calcium activity of DM GAD2 neurons in vivo indicates that these neurons are most active during REM sleep. Optogenetic stimulation of DM GAD2 neurons reliably triggered transitions into REM sleep from NREM sleep. Consistent with this, chemogenetic activation of DM GAD2 neurons increased the amount of REM sleep while inhibition suppressed its occurrence and enhanced NREM sleep. Anatomical tracing revealed that DM GAD2 neurons project to several areas involved in sleep / wake regulation including the wake-promoting locus coeruleus (LC) and the REM sleep-suppressing ventrolateral periaquaductal gray (vlPAG). Optogenetic activation of axonal projections from DM to LC, and DM to vlPAG was sufficient to induce REM sleep. Conclusion These experiments demonstrate that DM inhibitory neurons expressing GAD2 powerfully promote initiation of REM sleep in mice. These findings further characterize the dorsomedial medulla as a critical structure involved in REM sleep regulation and inform future investigations of the REM sleep circuitry. Support R01 HL149133

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Optogenetic activation of muscle contraction in vivo

10.1101/2020.07.07.192377 ◽

2020 ◽

Author(s):

Elahe Ganji ◽

C. Savio Chan ◽

Christopher W. Ward ◽

Megan L. Killian

Keyword(s):

Skeletal Muscle ◽

Electrical Stimulation ◽

Muscle Contraction ◽

Fluorescent Imaging ◽

Triceps Surae ◽

Light Activation ◽

Non Invasive ◽

Optogenetic Stimulation ◽

Stimulation Of

AbstractOptogenetics is an emerging alternative to traditional electrical stimulation to initiate action potentials in activatable cells both ex vivo and in vivo. Optogenetics has been commonly used in mammalian neurons and more recently, it has been adapted for activation of cardiomyocytes and skeletal muscle. Therefore, the aim of this study was to evaluate the stimulation feasibility and sustain isometric muscle contraction and limit decay for an extended period of time (1s), using non-invasive transdermal light activation of skeletal muscle (triceps surae) in vivo. We used inducible Cre recombination to target expression of Channelrhodopsin-2 (ChR2(H134R)-EYFP) in skeletal muscle (Acta1-Cre) in mice. Fluorescent imaging confirmed that ChR2 expression is localized in skeletal muscle and does not have specific expression in sciatic nerve branch, therefore, allowing for non-nerve mediated optical stimulation of skeletal muscle. We induced muscle contraction using transdermal exposure to blue light and selected 10Hz stimulation after controlled optimization experiments to sustain prolonged muscle contraction. Increasing the stimulation frequency from 10Hz to 40Hz increased the muscle contraction decay during prolonged 1s stimulation, highlighting frequency dependency and importance of membrane repolarization for effective light activation. Finally, we showed that optimized pulsed optogenetic stimulation of 10 Hz resulted in comparable ankle torque and contractile functionality to that of electrical stimulation. Our results demonstrate the feasibility and repeatability of non-invasive optogenetic stimulation of muscle in vivo and highlight optogenetic stimulation as a powerful tool for non-invasive in vivo direct activation of skeletal muscle.

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Optogenetic stimulation of Dbx1 neurons enhances the respiratory‐sympathetic coupling in in vivo CIH mice

The FASEB Journal ◽

10.1096/fasebj.2021.35.s1.04446 ◽

2021 ◽

Vol 35 (S1) ◽

Author(s):

Marlusa Karlen‐Amarante ◽

Alyssa Huff ◽

Nathan Baertsch ◽

Debora Colombari ◽

Jan‐Marino Ramirez

Keyword(s):

Optogenetic Stimulation ◽

Stimulation Of

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Ventral pallidal GABAergic neurons control wakefulness associated with motivation through the ventral tegmental pathway

Molecular Psychiatry ◽

10.1038/s41380-020-00906-0 ◽

2020 ◽

Author(s):

Ya-Dong Li ◽

Yan-Jia Luo ◽

Wei Xu ◽

Jing Ge ◽

Yoan Cherasse ◽

...

Keyword(s):

Dopaminergic Neurons ◽

Gabaergic Neurons ◽

Population Activity ◽

Lateral Habenula ◽

Optogenetic Stimulation ◽

Ventral Tegmental ◽

Stimulation Of

Abstract The ventral pallidum (VP) regulates motivation, drug addiction, and several behaviors that rely on heightened arousal. However, the role and underlying neural circuits of the VP in the control of wakefulness remain poorly understood. In the present study, we sought to elucidate the specific role of VP GABAergic neurons in controlling sleep–wake behaviors in mice. Fiber photometry revealed that the population activity of VP GABAergic neurons was increased during physiological transitions from non-rapid eye movement (non-REM, NREM) sleep to either wakefulness or REM sleep. Moreover, chemogenetic and optogenetic manipulations were leveraged to investigate a potential causal role of VP GABAergic neurons in initiating and/or maintaining arousal. In vivo optogenetic stimulation of VP GABAergic neurons innervating the ventral tegmental area (VTA) strongly promoted arousal via disinhibition of VTA dopaminergic neurons. Functional in vitro mapping revealed that VP GABAergic neurons, in principle, inhibited VTA GABAergic neurons but also inhibited VTA dopaminergic neurons. In addition, optogenetic stimulation of terminals of VP GABAergic neurons revealed that they promoted arousal by innervating the lateral hypothalamus, but not the mediodorsal thalamus or lateral habenula. The increased wakefulness chemogenetically evoked by VP GABAergic neuronal activation was completely abolished by pretreatment with dopaminergic D1 and D2/D3 receptor antagonists. Furthermore, activation of VP GABAergic neurons increased exploration time in both the open-field and light–dark box tests but did not modulate depression-like behaviors or food intake. Finally, chemogenetic inhibition of VP GABAergic neurons decreased arousal. Taken together, our findings indicate that VP GABAergic neurons are essential for arousal related to motivation.

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