Rest in The Zebrafish

The purpose and function of sleep has been the topic of discussion for several centuries. Though our understanding of the mechanisms underlying the propagation and maintenance of rest states has undergone significant improvement, much remains to be learned with regards to the effects of disrupted sleep on diseased states. A deeper understanding of the neural circuitry and associated phenotypes would allow for the identification of sleep-related pathologies as well as the development of therapies for individuals with sleep disorders. To this end, the zebrafish (danio rerio) pose a great advantage. In the adult animal, sleep is largely consolidated to dark phases. Sleep may be disrupted via environmental, pharmacological or genetic manipulations. Disrupted sleep rhythms in the adult animal are linked to changes in gene and protein expression, while behavioral measures of anxiety have produced mixed results. We propose that this variation is a result of the type of sleep disruption as well as the type of anxiety test employed. This beckons the need for further study of the effects of environmental and pharmacological manipulations on the sleep rhythms of the animal. Further, researchers must not rely solely on one test as a measure of stress or anxiety as it provides only a one-dimensional insight.

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Structure and function of neural networks in the retina

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102213 ◽

1988 ◽

Vol 46 ◽

pp. 26-27

Author(s):

Peter Sterling

Keyword(s):

Ganglion Cells ◽

Three Dimensional ◽

Structure And Function ◽

Synaptic Connections ◽

Visual Axis ◽

One Dimensional ◽

Cat Retina ◽

Ultrathin Sections ◽

And Function ◽

Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

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Expression and function of ErbB receptors and ligands in the pituitary

Endocrine Related Cancer ◽

10.1530/erc-11-0066 ◽

2011 ◽

Vol 18 (6) ◽

pp. R197-R211 ◽

Cited By ~ 42

Author(s):

Odelia Cooper ◽

George Vlotides ◽

Hidenori Fukuoka ◽

Mark I Greene ◽

Shlomo Melmed

Keyword(s):

Anterior Pituitary ◽

Kinase Inhibitors ◽

Erbb Receptors ◽

Receptor Ligands ◽

Paracrine Effects ◽

Tumor Subtypes ◽

Hormonal Secretion ◽

Gene And Protein Expression ◽

Erbb2 Receptor ◽

And Function

The role of ErbB family in discreet pituitary functions is reviewed. Several ErbB receptor ligands, EGF, TGFα, and heregulin are differentially expressed in normal gonadotroph and lacto-somatotroph lineages, and other elements of the anterior pituitary. ErbB receptors, i.e. EGFR and ErbB2, are also localized to the anterior pituitary with preferential EGFR lactosomatotroph expression. EGF regulates CRH and ACTH secretion and corticotroph proliferation as well as exhibiting autocrine and paracrine effects on gonadotrophs and on lactosomatotroph proliferation, gene and protein expression, and hormonal secretion. EGF and EGFR are expressed in both functioning and non-functioning pituitary adenomas, with higher expression in more aggressive tumor subtypes. ErbB2 receptor is detected in all tumor subtypes, particularly in invasive tumors. ErbB tyrosine kinase inhibitors regulate hormonal secretion, cell morphology, and proliferation in lacto-somatotroph tumors, reflecting the emerging application of targeted pituitary therapeutics.

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From Mice to Mainframes: Experimental Models for Investigation of the Intracardiac Nervous System

Journal of Cardiovascular Development and Disease ◽

10.3390/jcdd8110149 ◽

2021 ◽

Vol 8 (11) ◽

pp. 149

Author(s):

Matthew R. Stoyek ◽

Luis Hortells ◽

T. Alexander Quinn

Keyword(s):

Cardiovascular Disease ◽

Nervous System ◽

Computational Models ◽

Neural Circuitry ◽

Experimental Models ◽

Incomplete Knowledge ◽

Fundamental Understanding ◽

Health And Disease ◽

And Function ◽

Intracardiac Nervous System

The intracardiac nervous system (IcNS), sometimes referred to as the “little brain” of the heart, is involved in modulating many aspects of cardiac physiology. In recent years our fundamental understanding of autonomic control of the heart has drastically improved, and the IcNS is increasingly being viewed as a therapeutic target in cardiovascular disease. However, investigations of the physiology and specific roles of intracardiac neurons within the neural circuitry mediating cardiac control has been hampered by an incomplete knowledge of the anatomical organisation of the IcNS. A more thorough understanding of the IcNS is hoped to promote the development of new, highly targeted therapies to modulate IcNS activity in cardiovascular disease. In this paper, we first provide an overview of IcNS anatomy and function derived from experiments in mammals. We then provide descriptions of alternate experimental models for investigation of the IcNS, focusing on a non-mammalian model (zebrafish), neuron-cardiomyocyte co-cultures, and computational models to demonstrate how the similarity of the relevant processes in each model can help to further our understanding of the IcNS in health and disease.

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Cell Atlas technologies and insights into tissue architecture

Biochemical Journal ◽

10.1042/bcj20190341 ◽

2020 ◽

Vol 477 (8) ◽

pp. 1427-1442 ◽

Cited By ~ 4

Author(s):

Anna Wilbrey-Clark ◽

Kenny Roberts ◽

Sarah A. Teichmann

Keyword(s):

Single Cell ◽

Molecular Level ◽

Cell Types ◽

Tissue Architecture ◽

Robert Hooke ◽

Spatially Resolved ◽

Gene And Protein Expression ◽

Basic Biology ◽

And Function ◽

Fundamental Units

Since Robert Hooke first described the existence of ‘cells’ in 1665, scientists have sought to identify and further characterise these fundamental units of life. While our understanding of cell location, morphology and function has expanded greatly; our understanding of cell types and states at the molecular level, and how these function within tissue architecture, is still limited. A greater understanding of our cells could revolutionise basic biology and medicine. Atlasing initiatives like the Human Cell Atlas aim to identify all cell types at the molecular level, including their physical locations, and to make this reference data openly available to the scientific community. This is made possible by a recent technology revolution: both in single-cell molecular profiling, particularly single-cell RNA sequencing, and in spatially resolved methods for assessing gene and protein expression. Here, we review available and upcoming atlasing technologies, the biological insights gained to date and the promise of this field for the future.

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On the Nature of Sleep

The Bundahišn ◽

10.1093/oso/9780190879044.003.0033 ◽

2020 ◽

pp. 99-100

Author(s):

Domenico Agostini ◽

Samuel Thrope

Keyword(s):

Short Description ◽

The Creation ◽

Function Of Sleep ◽

And Function ◽

Proper Length

Chapters 19 and 19A contain a short description of the nature and function of sleep (xwāb). The chapters describe the creation of sleep and its appearance. They also proscribe the proper length of sleep as three or four recitations of one of the central Zoroastrian prayers.

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Metabolic endotoxemia promotes adipose dysfunction and inflammation in human obesity

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00277.2018 ◽

2019 ◽

Vol 316 (2) ◽

pp. E319-E332 ◽

Cited By ~ 13

Author(s):

Mercedes Clemente-Postigo ◽

Wilfredo Oliva-Olivera ◽

Leticia Coin-Aragüez ◽

Bruno Ramos-Molina ◽

Rosa María Giraldez-Perez ◽

...

Keyword(s):

Metabolic Diseases ◽

In Vitro Assays ◽

Low Grade ◽

Human Obesity ◽

Gene And Protein Expression ◽

And Function ◽

Adipose Dysfunction ◽

High Degree ◽

Metabolic Endotoxemia

Impaired adipose tissue (AT) lipid handling and inflammation is associated with obesity-related metabolic diseases. Circulating lipopolysaccharides (LPSs) from gut microbiota (metabolic endotoxemia), proposed as a triggering factor for the low-grade inflammation in obesity, might also be responsible for AT dysfunction. Nevertheless, this hypothesis has not been explored in human obesity. To analyze the relationship between metabolic endotoxemia and AT markers for lipogenesis, lipid handling, and inflammation in human obesity, 33 patients with obesity scheduled for surgery were recruited and classified according to their LPS levels. Visceral and subcutaneous AT gene and protein expression were analyzed and adipocyte and AT in vitro assays performed. Subjects with obesity with a high degree of metabolic endotoxemia had lower expression of key genes for AT function and lipogenesis ( SREBP1, FABP4, FASN, and LEP) but higher expression of inflammatory genes in visceral and subcutaneous AT than subjects with low LPS levels. In vitro experiments corroborated that LPS are responsible for adipocyte and AT inflammation and downregulation of PPARG, SCD, FABP4, and LEP expression and LEP secretion. Thus, metabolic endotoxemia influences AT physiology in human obesity by decreasing the expression of factors involved in AT lipid handling and function as well as by increasing inflammation.

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Therapeutic potential of TMS-induced plasticity in the prefrontal cortex

10.1093/oxfordhb/9780198568926.013.0038 ◽

2012 ◽

Author(s):

Stanislav R. Vorel ◽

Sarah H. Lisanby

Keyword(s):

Synaptic Plasticity ◽

Rational Design ◽

Therapeutic Potential ◽

Obsessive Compulsive ◽

Neural Structure ◽

Human Motor Cortex ◽

Compulsive Disorder ◽

Human Motor ◽

And Function ◽

Pharmacological Manipulations

This article discusses synaptic plasticity as a potential mechanism of enduring changes in function observed after relatively brief periods of repetitive (r)TMS. Plasticity is a use dependent enduring change in neural structure and function. The characteristics of plasticity are described in this article. Taking into account, the interactions between rTMS and pharmacological manipulations, this article explores how principles of synaptic plasticity may be exploited in the rational design of future rTMS paradigms in psychiatric disorders like major depressive disorder, obsessive-compulsive disorder, substance use disorders, schizophrenia etc. TMS is under active study in the treatment of a range of psychiatric and neurological disorders. Furthermore, this article discusses the implications for the interpretation of existing TMS literature and design of future interventions. TMS experiments of plasticity in the human motor cortex have been limited by the intensity and frequency of TMS protocols.

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The Neural Circuitry and Neurocognitive Development

The Oxford Handbook of Adolescent Substance Abuse ◽

10.1093/oxfordhb/9780199735662.013.011 ◽

2016 ◽

pp. 284-298

Author(s):

Reagan R. Wetherill ◽

Susan F. Tapert

Keyword(s):

Risk Taking ◽

Neural Circuitry ◽

Future Research ◽

Fiber Architecture ◽

Brain Functioning ◽

Functional Implications ◽

Brain Structure And Function ◽

And Function ◽

Asynchronous Maturation ◽

Adolescent Brain Development

This chapter focuses on adolescent brain development and associated functional implications. We focus on changes in brain tissue composition, fiber architecture and circuitry, and neurochemistry and discuss how these maturational processes affect adolescent brain functioning, sleep, cognition, and behaviors. Given the substantial developments that occur during adolescence, the effects of puberty and sex hormones on brain structure and function are reviewed, and literature on the effects of substance use on the adolescent brain are covered. The chapter reports on recent neuroimaging studies suggesting that atypical and/or asynchronous maturation patterns may contribute to adolescents’ proclivity for risk taking, heightened emotionality, and the emergence of psychopathology. Finally, future research opportunities are discussed.

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