Asymmetric neural coding revealed by
            in vivo
            calcium imaging in the honey bee brain

Left–right asymmetries are common properties of nervous systems. Although lateralized sensory processing has been well studied, information is lacking about how asymmetries are represented at the level of neural coding. Using in vivo functional imaging, we identified a population-level left–right asymmetry in the honey bee's primary olfactory centre, the antennal lobe (AL). When both antennae were stimulated via a frontal odour source, the inter-odour distances between neural response patterns were higher in the right than in the left AL. Behavioural data correlated with the brain imaging results: bees with only their right antenna were better in discriminating a target odour in a cross-adaptation paradigm. We hypothesize that the differences in neural odour representations in the two brain sides serve to increase coding capacity by parallel processing.

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The role of intra-articular neuronal CCR2 receptors in knee joint pain associated with experimental osteoarthritis in mice

Arthritis Research & Therapy ◽

10.1186/s13075-021-02486-y ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Shingo Ishihara ◽

Alia M. Obeidat ◽

David L. Wokosin ◽

Dongjun Ren ◽

Richard J. Miller ◽

...

Keyword(s):

Knee Joint ◽

Sensory Neuron ◽

Sensory Neurons ◽

Direct Stimulation ◽

Sensory Afferents ◽

Neuronal Marker ◽

The Right ◽

Experimental Osteoarthritis ◽

In Vivo Calcium Imaging

Abstract Background C–C chemokine receptor 2 (CCR2) signaling plays a key role in pain associated with experimental murine osteoarthritis (OA) after destabilization of the medial meniscus (DMM). Here, we aimed to assess if CCR2 expressed by intra-articular sensory neurons contributes to knee hyperalgesia in the early stages of the model. Methods DMM surgery was performed in the right knee of 10-week-old male wild-type (WT), Ccr2 null, or Ccr2RFP C57BL/6 mice. Knee hyperalgesia was measured using a Pressure Application Measurement device. CCR2 receptor antagonist (CCR2RA) was injected systemically (i.p.) or intra-articularly (i.a.) at different times after DMM to test its ability to reverse knee hyperalgesia. In vivo Ca2+ imaging of the dorsal root ganglion (DRG) was performed to assess sensory neuron responses to CCL2 injected into the knee joint cavity. CCL2 protein in the knee was measured by ELISA. Ccr2RFP mice and immunohistochemical staining for the pan-neuronal marker, protein gene product 9.5 (PGP9.5), or the sensory neuron marker, calcitonin gene-related peptide (CGRP), were used to visualize the location of CCR2 on intra-articular afferents. Results WT, but not Ccr2 null, mice displayed knee hyperalgesia 2–16 weeks after DMM. CCR2RA administered i.p. alleviated established hyperalgesia in WT mice 4 and 8 weeks after surgery. Intra-articular injection of CCL2 excited sensory neurons in the L4-DRG, as determined by in vivo calcium imaging; responses to CCL2 increased in mice 20 weeks after DMM. CCL2, but not vehicle, injected i.a. rapidly caused transient knee hyperalgesia in naïve WT, but not Ccr2 null, mice. Intra-articular CCR2RA injection also alleviated established hyperalgesia in WT mice 4 and 7 weeks after surgery. CCL2 protein was elevated in the knees of both WT and Ccr2 null mice 4 weeks after surgery. Co-expression of CCR2 and PGP9.5 as well as CCR2 and CGRP was observed in the lateral synovium of naïve mice; co-expression was also observed in the medial compartment of knees 8 weeks after DMM. Conclusions The findings suggest that CCL2-CCR2 signaling locally in the joint contributes to knee hyperalgesia in experimental OA, and it is in part mediated through direct stimulation of CCR2 expressed by intra-articular sensory afferents.

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The significance of the detection of oxidative and reducing tissue enzymes for questions of localization in the brain

Kazan medical journal ◽

10.17816/kazmj77085 ◽

1927 ◽

Vol 23 (6-7) ◽

pp. 613-621

Author(s):

М. Bielschowsky ◽

М. Rose

Keyword(s):

Nervous System ◽

The Right ◽

The Brain

Histology of the nervous system is served, for the purpose of research, almost exclusively by stained slices from fixed objects. As fixing agents, mainly alcohol, formaldehyde and mixtures of chromium salts are used, which produce more or less fast clotting of tissue colloids, as a result of which the in vivo structure of cells with their processes is very much changed. To what extent our preparations give us the right to conclude about the living structure of cells and especially about the processes running or already running intra vitam is an old and much debated problem.

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Use of Polyamidoamine Dendrimers in Brain Diseases

Molecules ◽

10.3390/molecules23092238 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2238 ◽

Cited By ~ 15

Author(s):

Maria Florendo ◽

Alexander Figacz ◽

Bhairavi Srinageshwar ◽

Ajit Sharma ◽

Douglas Swanson ◽

...

Keyword(s):

Pamam Dendrimers ◽

Brain Diseases ◽

Surface Functional Groups ◽

Polyamidoamine Dendrimers ◽

Effective Delivery ◽

The Right ◽

The Brain ◽

Reproducible Manner

Polyamidoamine (PAMAM) dendrimers are one of the smallest and most precise nanomolecules available today, which have promising applications for the treatment of brain diseases. Each aspect of the dendrimer (core, size or generation, size of cavities, and surface functional groups) can be precisely modulated to yield a variety of nanocarriers for delivery of drugs and genes to brain cells in vitro or in vivo. Two of the most important criteria to consider when using PAMAM dendrimers for neuroscience applications is their safety profile and their potential to be prepared in a reproducible manner. Based on these criteria, features of PAMAM dendrimers are described to help the neuroscience researcher to judiciously choose the right type of dendrimer and the appropriate method for loading the drug to form a safe and effective delivery system to the brain.

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5HT2 Receptors in Cerebral Cortex of Migraineurs Studied Using PET and 18F-Fluorosetoperone

Cephalalgia ◽

10.1046/j.1468-2982.1995.015002104.x ◽

1995 ◽

Vol 15 (2) ◽

pp. 104-108 ◽

Cited By ~ 21

Author(s):

H Chabriat ◽

A Tehindrazanarivelo ◽

P Vera ◽

Y Samson ◽

S Pappata ◽

...

Keyword(s):

Healthy Subjects ◽

Occipital Cortex ◽

Emission Tomography ◽

Specific Distribution ◽

Positron Emission ◽

Migraine Pathogenesis ◽

5Ht2 Receptors ◽

The Right ◽

The Brain

Since the brain 5HT2 receptors might be implicated in migraine pathogenesis, we have used positron emission tomography and 18F-fluorosetoperone, a 5HT2 specific radioligand, to investigate in vivo the cortical 5HT2 receptors in migraine subjects. Nine migraineurs who had either migraine with and without aura ( n = 5) or only migraine without aura ( n = 4) were studied between attacks. Twelve unmedicated healthy subjects of similar mean age were used as controls. Brain radioactivity was measured after 18F-setoperone IV injection for 90 min. A decrease of the regional specific distribution volumes (SDV) of the ligand was observed both in migraineurs and in controls. The age adjusted group means of SDV did not differ between patients and controls for the whole and for the right or left frontal, temporal, parietal and occipital cortex. These results suggest that cortical 5HT2 receptors may be unaltered between attacks in migraine sufferers.

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A size principle for recruitment of Drosophila leg motor neurons

eLife ◽

10.7554/elife.56754 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 6

Author(s):

Anthony W Azevedo ◽

Evyn S Dickinson ◽

Pralaksha Gurung ◽

Lalanti Venkatasubramanian ◽

Richard S Mann ◽

...

Keyword(s):

Motor Neurons ◽

Functional Organization ◽

Fruit Fly ◽

The Body ◽

Hierarchical Organization ◽

Size Principle ◽

And Behavior ◽

In Vivo Calcium Imaging ◽

The Brain

To move the body, the brain must precisely coordinate patterns of activity among diverse populations of motor neurons. Here, we use in vivo calcium imaging, electrophysiology, and behavior to understand how genetically-identified motor neurons control flexion of the fruit fly tibia. We find that leg motor neurons exhibit a coordinated gradient of anatomical, physiological, and functional properties. Large, fast motor neurons control high force, ballistic movements while small, slow motor neurons control low force, postural movements. Intermediate neurons fall between these two extremes. This hierarchical organization resembles the size principle, first proposed as a mechanism for establishing recruitment order among vertebrate motor neurons. Recordings in behaving flies confirmed that motor neurons are typically recruited in order from slow to fast. However, we also find that fast, intermediate, and slow motor neurons receive distinct proprioceptive feedback signals, suggesting that the size principle is not the only mechanism that dictates motor neuron recruitment. Overall, this work reveals the functional organization of the fly leg motor system and establishes Drosophila as a tractable system for investigating neural mechanisms of limb motor control.

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Identification of Zebrafish Calcium Toolkit Genes and their Expression in the Brain

Genes ◽

10.3390/genes10030230 ◽

2019 ◽

Vol 10 (3) ◽

pp. 230 ◽

Cited By ~ 5

Author(s):

Iga Wasilewska ◽

Rishikesh Kumar Gupta ◽

Oksana Palchevska ◽

Jacek Kuźnicki

Keyword(s):

Developmental Stages ◽

Model Organism ◽

Network Activity ◽

Mrna Levels ◽

Adult Zebrafish ◽

Neuronal Function ◽

In Vivo Calcium Imaging ◽

The Brain

Zebrafish are well-suited for in vivo calcium imaging because of the transparency of their larvae and the ability to express calcium probes in various cell subtypes. This model organism has been used extensively to study brain development, neuronal function, and network activity. However, only a few studies have investigated calcium homeostasis and signaling in zebrafish neurons, and little is known about the proteins that are involved in these processes. Using bioinformatics analysis and available databases, the present study identified 491 genes of the zebrafish Calcium Toolkit (CaTK). Using RNA-sequencing, we then evaluated the expression of these genes in the adult zebrafish brain and found 380 hits that belonged to the CaTK. Based on quantitative real-time polymerase chain reaction arrays, we estimated the relative mRNA levels in the brain of CaTK genes at two developmental stages. In both 5 dpf larvae and adult zebrafish, the highest relative expression was observed for tmbim4, which encodes a Golgi membrane protein. The present data on CaTK genes will contribute to future applications of zebrafish as a model for in vivo and in vitro studies of Ca2+ signaling.

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Decoding Drosophila Circadian Pacemaker Circuit

10.20944/preprints201905.0299.v1 ◽

2019 ◽

Author(s):

Anatoly Kozlov ◽

Emi Nagoshi

Keyword(s):

Calcium Imaging ◽

Neural Circuits ◽

Circadian Pacemaker ◽

Long Span ◽

Direct Observations ◽

Current Challenge ◽

Rhythmic Behavior ◽

In Vivo Calcium Imaging ◽

The Brain

Drosophila circadian circuit is one of the best described neural circuits but is complex enough to obscure our understanding of how it actually works. Animals’ rhythmic behavior, the seemingly simple outcome of their internal clocks, relies on the interaction of heterogeneous clock neurons that are spread across the brain. Direct observations of their coordinated network interactions can bring us forward in understanding the circuit. The current challenge is to observe activity of each of these neurons over a long span of time –hours to days– in live animals. Here we review the progress in circadian circuit interrogation powered by in vivo calcium imaging.

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Horses show individual level lateralisation when inspecting an unfamiliar and unexpected stimulus

PLoS ONE ◽

10.1371/journal.pone.0255688 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0255688

Author(s):

Paolo Baragli ◽

Chiara Scopa ◽

Martina Felici ◽

Adam R. Reddon

Keyword(s):

Right Hemisphere ◽

Population Level ◽

Emotional Valence ◽

Avoidance Reaction ◽

Sample Population ◽

Individual Level ◽

Inflated Balloon ◽

The Right ◽

The Brain ◽

Unexpected Stimulus

Animals must attend to a diverse array of stimuli in their environments. The emotional valence and salience of a stimulus can affect how this information is processed in the brain. Many species preferentially attend to negatively valent stimuli using the sensory organs on the left side of their body and hence the right hemisphere of their brain. Here, we investigated the lateralisation of visual attention to the rapid appearance of a stimulus (an inflated balloon) designed to induce an avoidance reaction and a negatively valent emotional state in 77 Italian saddle horses. Horses’ eyes are laterally positioned on the head, and each eye projects primarily to the contralateral hemisphere, allowing eye use to be a proxy for preferential processing in one hemisphere of the brain. We predicted that horses would inspect the novel and unexpected stimulus with their left eye and hence right hemisphere. We found that horses primarily inspected the balloon with one eye, and most horses had a preferred eye to do so, however, we did not find a population level tendency for this to be the left or the right eye. The strength of this preference tended to decrease over time, with the horses using their non-preferred eye to inspect the balloon increasingly as the trial progressed. Our results confirm a lateralised eye use tendency when viewing negatively emotionally valent stimuli in horses, in agreement with previous findings. However, there was not any alignment of lateralisation at the group level in our sample, suggesting that the expression of lateralisation in horses depends on the sample population and testing context.

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The brain structure and neurosecretory cells of noctuid moth Anadevidia peponis: Noctuidae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159722 ◽

1990 ◽

Vol 48 (3) ◽

pp. 436-437

Author(s):

M. Sato ◽

Y. Ogawa ◽

M. Sasaki ◽

T. Matsuo

Keyword(s):

Biological Clock ◽

Virgin Female ◽

Basic Structure ◽

Fixed Time ◽

Neurosecretory Cells ◽

Nerve Cells ◽

Noctuid Moth ◽

The Right ◽

20 Nm ◽

The Brain

A virgin female of the noctuid moth, a kind of noctuidae that eats cucumis, etc. performs calling at a fixed time of each day, depending on the length of a day. The photoreceptors that induce this calling are located around the neurosecretory cells (NSC) in the central portion of the protocerebrum. Besides, it is considered that the female’s biological clock is located also in the cerebral lobe. In order to elucidate the calling and the function of the biological clock, it is necessary to clarify the basic structure of the brain. The observation results of 12 or 30 day-old noctuid moths showed that their brains are basically composed of an outer and an inner portion-neural lamella (about 2.5 μm) of collagen fibril and perineurium cells. Furthermore, nerve cells surround the cerebral lobes, in which NSCs, mushroom bodies, and central nerve cells, etc. are observed. The NSCs are large-sized (20 to 30 μm dia.) cells, which are located in the pons intercerebralis of the head section and at the rear of the mushroom body (two each on the right and left). Furthermore, the cells were classified into two types: one having many free ribosoms 15 to 20 nm in dia. and the other having granules 150 to 350 nm in dia. (Fig. 1).

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Effect of pH and inhibitors on beta-amyloid fibril assembly

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166221 ◽

1996 ◽

Vol 54 ◽

pp. 752-753

Author(s):

Beverly E. Maleeff ◽

Timothy K. Hart ◽

Stephen J. Wood ◽

Ronald Wetzel

Keyword(s):

Amyloid Fibril ◽

Peptide Fragment ◽

Hydrophobic Peptides ◽

Amyloid Fibril Formation ◽

Effects Of Ph ◽

Severity Of The Disease ◽

Kinetics Of ◽

The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

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