Morphological Plasticity of the Retina of Viperidae Snakes Is Associated With Ontogenetic Changes in Ecology and Behavior
In this study, we compared the density and distribution of photoreceptors and ganglion cell layer (GCL) cells in whole-mounted retinas of two viperid snakes, the lancehead Bothrops jararaca and the rattlesnake Crotalus durissus, and we estimated the upper limits of spatial resolving power based on anatomical data. The ground-dwelling C. durissus inhabits savannah-like habitats and actively searches for places to hide before using the sit-and-wait hunting strategy to ambush rodents. B. jararaca inhabits forested areas and has ontogenetic changes in ecology and behavior. Adults are terrestrial and use similar hunting strateg...
Source: Frontiers in Neuroanatomy - January 29, 2022 Category: Neurology Source Type: research
Axonal and Dendritic Morphology of Excitatory Neurons in Layer 2/3 Mouse Barrel Cortex Imaged Through Whole-Brain Two-Photon Tomography and Registered to a Digital Brain Atlas
Communication between cortical areas contributes importantly to sensory perception and cognition. On the millisecond time scale, information is signaled from one brain area to another by action potentials propagating across long-range axonal arborizations. Here, we develop and test methodology for imaging and annotating the brain-wide axonal arborizations of individual excitatory layer 2/3 neurons in mouse barrel cortex through single-cell electroporation and two-photon serial section tomography followed by registration to a digital brain atlas. Each neuron had an extensive local axon within the barrel cortex. In addition,...
Source: Frontiers in Neuroanatomy - January 25, 2022 Category: Neurology Source Type: research
Type II Opsins in the Eye, the Pineal Complex and the Skin of Xenopus laevis: Using Changes in Skin Pigmentation as a Readout of Visual and Circadian Activity
The eye, the pineal complex and the skin are important photosensitive organs. The African clawed frog, Xenopus laevis, senses light from the environment and adjusts skin color accordingly. For example, light reflected from the surface induces camouflage through background adaptation while light from above produces circadian variation in skin pigmentation. During embryogenesis, background adaptation, and circadian skin variation are segregated responses regulated by the secretion of α-melanocyte-stimulating hormone (α-MSH) and melatonin through the photosensitivity of the eye and pineal complex, respectively. Changes in t...
Source: Frontiers in Neuroanatomy - January 21, 2022 Category: Neurology Source Type: research
Seeing the Forest and Its Trees Together: Implementing 3D Light Microscopy Pipelines for Cell Type Mapping in the Mouse Brain
The brain is composed of diverse neuronal and non-neuronal cell types with complex regional connectivity patterns that create the anatomical infrastructure underlying cognition. Remarkable advances in neuroscience techniques enable labeling and imaging of these individual cell types and their interactions throughout intact mammalian brains at a cellular resolution allowing neuroscientists to examine microscopic details in macroscopic brain circuits. Nevertheless, implementing these tools is fraught with many technical and analytical challenges with a need for high-level data analysis. Here we review key technical considera...
Source: Frontiers in Neuroanatomy - January 16, 2022 Category: Neurology Source Type: research
A Baboon Brain Atlas for Magnetic Resonance Imaging and Positron Emission Tomography Image Analysis
The olive baboon (Papio anubis) is phylogenetically proximal to humans. Investigation into the baboon brain has shed light on the function and organization of the human brain, as well as on the mechanistic insights of neurological disorders such as Alzheimer’s and Parkinson’s. Non-invasive brain imaging, including positron emission tomography (PET) and magnetic resonance imaging (MRI), are the primary outcome measures frequently used in baboon studies. PET functional imaging has long been used to study cerebral metabolic processes, though it lacks clear and reliable anatomical information. In contrast, MRI provides a c...
Source: Frontiers in Neuroanatomy - January 14, 2022 Category: Neurology Source Type: research
Asymmetric Distributions of Achromatic Bipolar Cells in the Mouse Retina
In conclusion, we found that a subset of achromatic bipolar cells is asymmetrically distributed in the mouse retina, suggesting their unique roles in achromatic visual processing. (Source: Frontiers in Neuroanatomy)
Source: Frontiers in Neuroanatomy - January 13, 2022 Category: Neurology Source Type: research
Identification of Mineralocorticoid Receptors, Aldosterone, and Its Processing Enzyme CYP11B2 on Parasympathetic and Sympathetic Neurons in Rat Intracardiac Ganglia
Recent interest has focused on the mineralocorticoid receptor (MR) and its impact on the myocardium and the performance of the heart. However, there is a lack of evidence about MR expression and its endogenous ligand aldosterone synthesis with specific regard to the intrinsic cardiac nervous system. Therefore, we looked for evidence of MR and aldosterone in sympathetic and parasympathetic neurons of intracardiac ganglia. Tissue samples from rat heart atria were subjected to conventional reverse-transcriptase polymerase chain reaction (PCR), Western blot, and double immunofluorescence confocal analysis of MR, corticosterone...
Source: Frontiers in Neuroanatomy - January 11, 2022 Category: Neurology Source Type: research
Corrigendum: Perforating Arteries of the Lemniscal Trigone: A Microsurgical Neuroanatomic Description
(Source: Frontiers in Neuroanatomy)
Source: Frontiers in Neuroanatomy - January 5, 2022 Category: Neurology Source Type: research
Advanced Dissection Lab for Neuroanatomy Training
(Source: Frontiers in Neuroanatomy)
Source: Frontiers in Neuroanatomy - January 5, 2022 Category: Neurology Source Type: research
Axonal Projection Patterns of the Dorsal Interneuron Populations in the Embryonic Hindbrain
In this study, we reviewed the available data regarding the association between the specification of early-born dorsal interneuron subpopulations in the hindbrain and their axonal circuitry development and fate, as well as the present existing knowledge on molecular effectors underlying the process of axonal growth. (Source: Frontiers in Neuroanatomy)
Source: Frontiers in Neuroanatomy - December 24, 2021 Category: Neurology Source Type: research
Recollections on the Origins and Development of the Prosomeric Model
This article explains the progressive academic and scientific antecedents leading LP to this collaboration and its subsequent developments. Other antecedents due to earlier neuroembryologists that also proposed neuromeric brain models since the late 19th century, as well as those who defended the alternative columnar model, are presented and explained. The circumstances that apparently caused the differential success of the neuromeric models in the recent neurobiological field are also explored. (Source: Frontiers in Neuroanatomy)
Source: Frontiers in Neuroanatomy - December 24, 2021 Category: Neurology Source Type: research
A Whole-Brain Connectivity Map of VTA and SNc Glutamatergic and GABAergic Neurons in Mice
The glutamatergic and GABAergic neurons in the ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) mediated diverse brain functions. However, their whole-brain neural connectivity has not been comprehensively mapped. Here we used the virus tracers to characterize the whole-brain inputs and outputs of glutamatergic and GABAergic neurons in VTA and SNc. We found that these neurons received similar inputs from upstream brain regions, but some quantitative differences were also observed. Neocortex and dorsal striatum provided a greater share of input to VTA glutamatergic neurons. Periaqueductal gray and later...
Source: Frontiers in Neuroanatomy - December 23, 2021 Category: Neurology Source Type: research
The Functional Anatomy of the Cornea and Anterior Chamber in Lampreys: Insights From the Pouched Lamprey, Geotria australis (Geotriidae, Agnatha)
This study investigates the functional morphology of the cornea and anterior chamber of G. australis, which is specialised compared to its northern hemisphere counterparts. Using light microscopy, scanning and transmission electron microscopy and microcomputed tomography, the cornea is found to be split into a primary spectacle (dermal cornea) and a scleral cornea (continuous with the scleral eyecup), separated by a mucoid layer bounded on each side by a basement membrane. A number of other specialisations are described including mucin-secreting epithelial cells and microholes, four types of stromal sutures for the inhibit...
Source: Frontiers in Neuroanatomy - December 23, 2021 Category: Neurology Source Type: research
High-Throughput Strategy for Profiling Sequential Section With Multiplex Staining of Mouse Brain
In this study, we introduced a pipeline to acquire anatomical and histological information quickly and efficiently from serial sections. First, we developed a serial brain-slice-staining method to stain serial sections and obtained more than 98.5% of slices with high integrity. Subsequently, using the self-developed analysis software, we registered and quantified the signals of imaged sections to the Allen Mouse Brain Common Coordinate Framework, which is compatible with multimodal images and slant section planes. Finally, we validated the pipeline with immunostaining by analyzing the activity variance in the whole brain d...
Source: Frontiers in Neuroanatomy - December 23, 2021 Category: Neurology Source Type: research
Whole-Brain Reconstruction of Neurons in the Ventral Pallidum Reveals Diverse Projection Patterns
In this study, we used recently developed progress in robust sparse labeling and fluorescence micro-optical sectioning tomography imaging system (fMOST) to label mediodorsal thalamus-projecting neurons in the VP and obtain high-resolution whole-brain imaging data. Based on these data, we reconstructed VP neurons and classified them into three types according to their fiber projection patterns. We systematically compared the axonal density in various downstream centers and analyzed the soma distribution and dendritic morphologies of the various subtypes at the single neuron level. Our study thus provides a detailed characte...
Source: Frontiers in Neuroanatomy - December 16, 2021 Category: Neurology Source Type: research
