Age-related histological changes in neurosecretory cells in the supraoesophageal ganglion of Nereis virens (Annelida, Polychaeta)

1980 ◽  
Vol 58 (10) ◽  
pp. 1735-1740 ◽  
Author(s):  
Kathryn Bell ◽  
Joan R. Marsden
Keyword(s):  
Light Microscopy ◽  
Developmental Stages ◽  
Cell Types ◽  
Staining Intensity ◽  
Neurosecretory Cells ◽  
Histological Changes ◽  
Nereis Virens ◽  
Age Related ◽  
P Cells ◽  
The Brain

The supraoesophageal ganglion of Nereis virens has been surveyed by light microscopy to determine the locations of probable neurosecretory cells. Neurons reacting with paraldehyde fuchsin are found scattered throughout the brain, but the majority are accumulated posteriorly in nucleus 20. This nucleus was examined in some detail, and the histology of four cell types is described. Two types (p and r) are strongly paraldehyde-fuchsin-positive, and may be secretory. On the basis of other staining characteristics, and uptake of labelled cystine, it is concluded that p cells are rich in cystine and (or) cysteine. A comparison of juvenile and adult brains revealed that the same cell types exist at both developmental stages, but that p and r cells increase in number and staining intensity with age. These findings are not consistent with the notion that these particular cells are the source of a "juvenile hormone' ' which has been reported to exist in nereids. Rather it is suggested that the described cells are producers of a maturation and (or) spawning hormone.

HISTOMORPHOLOGICAL CHANGES IN THE BRAIN IN RELATION TO OVARIAN CYCLE OF FRESHWATER CRAB, BARYTELPHUSA CUNICULARIS

2017 ◽  
Vol 23 (1) ◽  
Author(s):  
C.A. JAWALE
Keyword(s):  
Staining Intensity ◽  
Neurosecretory Cells ◽  
Ovarian Cycle ◽  
Secretory Product ◽  
Freshwater Crab ◽  
Intensity Index ◽  
Cytoplasmic Material ◽  
Histomorphological Changes ◽  
Cyclic Changes ◽  
The Brain

Ovarian maturation by neurosecretory cells in the brain of freshwater crab, Barytelphusa cunicularis have been examined. The histological scrutiny of the brain of Barytelphusa cunicularis related with three types (A, B and C) of neurosecretory cells, which are classified on the basis of size, shape and tinctorial characters. All these types of cells marked annual cyclic changes of cytoplasmic material in association with ovarian cycle. The activity of these cells has been correlated with the ovarian cycle. They are distinguishable by their size, nature locations, shape, nucleus position, cell measure and the secretory product in the cytoplasm. The result indicates that the neurosecretory A, B and C cells of the brain seen involved in the process of mating ovulation. The neurosecretory materials staining intensity index of these cells is described.

scholarly journals The islet ghrelin cell

2013 ◽  
Vol 52 (1) ◽  
pp. R35-R49 ◽  
Author(s):  
Nils Wierup ◽  
Frank Sundler ◽  
R Scott Heller
Keyword(s):  
Molecular Mechanisms ◽  
Developmental Stages ◽  
Developmental Regulation ◽  
Genetic Regulation ◽  
Cell Types ◽  
Human Islets ◽  
Histochemical Staining ◽  
Pancreatic Tumours ◽  
Age Related ◽  
Staining Methods

The islets of Langerhans are key regulators of glucose homeostasis and have been known as a structure for almost one and a half centuries. During the twentieth century several different cell types were described in the islets of different species and at different developmental stages. Six cell types with identified hormonal product have been described so far by the use of histochemical staining methods, transmission electron microscopy, and immunohistochemistry. Thus, glucagon-producing α-cells, insulin-producing β-cells, somatostatin-producing δ-cells, pancreatic polypeptide-producing PP-cells, serotonin-producing enterochromaffin-cells, and gastrin-producing G-cells have all been found in the mammalian pancreas at least at some developmental stage. Species differences are at hand and age-related differences are also to be considered. Eleven years ago a novel cell type, the ghrelin cell, was discovered in the human islets. Subsequent studies have shown the presence of islet ghrelin cells in several animals, including mouse, rat, gerbils, and fish. The developmental regulation of ghrelin cells in the islets of mice has gained a lot of interest and several studies have added important pieces to the puzzle of molecular mechanisms and the genetic regulation that lead to differentiation into mature ghrelin cells. A body of evidence has shown that ghrelin is an insulinostatic hormone, and the potential for blockade of ghrelin signalling as a therapeutic avenue for type 2 diabetes is intriguing. Furthermore, ghrelin-expressing pancreatic tumours have been reported and ghrelin needs to be taken into account when diagnosing pancreatic tumours. In this review article, we summarise the knowledge about islet ghrelin cells obtained so far.

Cortical Cartography

Biofeedback ◽  
2010 ◽  
Vol 38 (1) ◽  
pp. 9-12 ◽  
Author(s):  
David A. Kaiser
Keyword(s):  
Light Microscopy ◽  
Coordinate System ◽  
Operant Conditioning ◽  
Spherical Harmonic ◽  
Cell Types ◽  
Spherical Harmonic Expansion ◽  
3 Dimensional ◽  
Brodmann Areas ◽  
The Brain

Abstract Architecture is one part science, one part craft, and two parts art.—David Rutten This article describes the investigation of structural-functional associations in the brain. Using light microscopy in 1909, Brodmann divided the human and primate brains into dozens of areas based on cell types and distributions, which has since been supplemented by a 3-dimensional coordinate system, an xyz system of millimeter distances. A number of electroencephalograph tomographic (volume) solutions exist, and this article explains the Brodmann montage developed by the author using the spherical harmonic expansion solution by Pascual-Marqui. The author describes his approach to training specific Brodmann areas with electroencephalograhic operant conditioning or feedback.

Morphology and histology of the endocrine glands of Zootermopsis angusticollis Hagen (Isoptera)

1972 ◽  
Vol 50 (12) ◽  
pp. 1537-1547 ◽  
Author(s):  
Cedric Gillott ◽  
Chih-Ming Yin
Keyword(s):  
Cell Types ◽  
Cell Number ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Endocrine Glands ◽  
Histological Changes ◽  
Secretory Cycle ◽  
Zootermopsis Angusticollis ◽  
Primary Reproductives ◽  
Median Neurosecretory Cells

The morphology and histology of the endocrine glands of the various castes of Zootermopsis angmticollis were examined. Six types of median neurosecretory cells are distinguishable by size and stain affinity. No differences in the relative numbers of these cell types among castes can be seen. It is postulated that they may be different forms of the same cell during its synthetic and secretory cycle. Lateral neurosecretory cells can be identified consistently only in mature primary reproductives of both sexes. In the corpora cardiaca two types of cells occur; the fuchsinophilic cells are distributed generally whereas the cells that take up counterstain are restricted to the center of the gland. Intercellular neurosecretory cell product is found throughout the gland. No histological changes associated with the formation of particular castes were observed. The corpora allata (CA) vary in size and histological appearance according to caste but not sex. The CA of reproductives (primary and supplementary) and presoldiers are larger than those of juveniles of the same instar; those of soldiers are about the same size as those of the corresponding juvenile stage. These size increases are due mainly to changes in the ratio cytoplasmic diameter: nuclear diameter of the constituent cells and not to an increase in cell number. The H-shaped molt glands, which, as in other pterygote insects, disappear within a few days of the imaginal molt, are composed of a large prothoracic portion and a smaller cephalic ('ventral gland') portion extending anteriorly and dorsally. Histologically the two components are indistinguishable. Running through the glands are thin strands of muscle.

scholarly journals 3D Neuronal Mitochondrial Morphology in Axons, Dendrites, and Somata of the Aging Mouse Hippocampus

2021 ◽  
Author(s):  
Julie Faitg ◽  
Clay Lacefield ◽  
Tracey Davey ◽  
Kathryn White ◽  
Ross Laws ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Cell Types ◽  
Aging Brain ◽  
Mitochondrial Morphology ◽  
Mitochondrial Network ◽  
Age Related ◽  
Mouse Hippocampus ◽  
Old Mice ◽  
The Brain

The brain′s ability to process complex informations relies on the constant supply of energy through aerobic respiration by mitochondria. Neurons contain three anatomically distinct compartments – the soma, dendrites, and projecting axons – which have different energetic and biochemical requirements, as well as different mitochondrial morphologies in cultured systems. Here we apply a quantitative three-dimensional electron microscopy approach to map mitochondrial network morphology and complexity in the mouse brain. We examine three neuronal sub–compartments – the soma, dendrites, myelinated axons – in the dentate gyrus and CA1 of the mouse hippocampus, two subregions with distinct principal cell types and functions. We also establish compartment-specific differences in mitochondrial morphology across these cell types between young and old mice, highlighting differences in age-related morphological recalibrations. Overall, these data define the nature of the neuronal mitochondrial network in the mouse hippocampus, providing a foundation to examine the role of mitochondrial morpho–function in the aging brain.

scholarly journals Determinants of drug entry into the developing brain

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 1372 ◽  
Author(s):  
Liam Koehn ◽  
Mark Habgood ◽  
Yifan Huang ◽  
Katarzyna Dziegielewska ◽  
Norman Saunders
Keyword(s):  
Abc Transporters ◽  
Chronic Treatment ◽  
Drug Exposure ◽  
Developmental Stages ◽  
Fetal Brain ◽  
Developing Brain ◽  
Adult Brain ◽  
Sprague Dawley ◽  
Age Related ◽  
The Brain

Background: A major concern for clinicians in prescribing medications to pregnant women and neonates is the possibility that drugs might have damaging effects, particularly on long-term brain development. Current understanding of drug permeability at placental and blood-brain barriers during development is poor. In adults, ABC transporters limit many drugs from entering the brain; however, little is known about their function during development. Methods: The transfer of clinically relevant doses of paracetamol (acetaminophen), digoxin and cimetidine into the brain and cerebrospinal fluid (CSF) was estimated using radiolabelled drugs in Sprague Dawley rats at three developmental stages: E19, P4 and adult. Drugs were applied intraperitoneally either acutely or following chronic exposure (for five days). Entry into brain, CSF and transfer across the placenta was measured and compared to three markers (L-glucose, sucrose, glycerol) that cross barriers by “passive diffusion”. The expression of ABC transporters in the brain, choroid plexus and placenta was estimated using RT-qPCR. Results: All three drugs entered the developing brain and CSF in higher amounts than the adult brain and CSF. Comparisons with “passive” permeability markers suggested that this might be due to age-related differences in the functional capacity of ABC-efflux mechanisms. In adult animals, chronic treatment reduced digoxin (12% to 5%, p<0.01) and paracetamol (30% to 21%, p<0.05) entry compared to acute treatment, with the decrease in digoxin entry correlating with up-regulation of efflux transporter abcb1a (PGP). In fetal and newborn animals, no gene up-regulation or transfer decreases were observed. Instead, chronic paracetamol treatment resulted in increased transfer into the fetal brain (66% to 104%, p<0.001). Conclusions: These results suggest that the developing brain may be more at risk from acute drug exposure than the adult brain due to reduced efflux capacity and at greater risk from chronic treatment due to a lack of efflux mechanism regulatory capacity.

scholarly journals Relationship Between Gonad Condition and Neurosecretory Cell Activity in the Green-Lipped Mussel, Perna canaliculus

2014 ◽  
Vol 18 (2) ◽  
pp. 135-148 ◽  
Author(s):  
S Mahmud ◽  
PV Mladenov ◽  
SC Chakraborty ◽  
MAR Faruk
Keyword(s):  
Neurosecretory Cell ◽  
Cell Activity ◽  
Gonad Development ◽  
Cell Types ◽  
Staining Intensity ◽  
Neurosecretory Cells ◽  
Gonad Maturation ◽  
Colour Intensity ◽  
Perna Canaliculus ◽  
The Relationship

The relationship between the activity of neurosecretory cells and gonad development of Perna canaliculus was investigated. The variation in staining intensity of the neurosecretory cells in different ganglia was evaluated. Changes in staining intensity of neurosecretory cells (NSC) were correlated with gonad development. The variation in colour intensity (CI) resulted from differences in the amount of secretory materials within the NSCs. The neurosecretory cell types A and B showed a similar pattern of staining intensity, and showed correlation with gametogenesis and spawning. At the beginning of gonad development, these cells possessed very few granules and the number of granules in the cells increased with gonad maturation. The staining intensity decreased in A and B- cells just after spawning. Cell types C and D did not show any substantial changes in colour intensity with gonad changes.DOI: http://dx.doi.org/10.3329/pa.v18i2.18169 Progress. Agric. 18(2): 135 - 148, 2007

scholarly journals Ocular Neurodegenerative Diseases: Interconnection between Retina and Cortical Areas

Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2394
Author(s):  
Nicoletta Marchesi ◽  
Foroogh Fahmideh ◽  
Federica Boschi ◽  
Alessia Pascale ◽  
Annalisa Barbieri
Keyword(s):  
Neurodegenerative Diseases ◽  
Light Stimulus ◽  
The Elderly ◽  
Cell Types ◽  
Age Related Macular Degeneration ◽  
Age Related ◽  
Ocular Disorders ◽  
Progressive Neurodegeneration ◽  
Underlying Mechanisms ◽  
The Brain

The possible interconnection between the eye and central nervous system (CNS) has been a topic of discussion for several years just based on fact that the eye is properly considered an extension of the brain. Both organs consist of neurons and derived from a neural tube. The visual process involves photoreceptors that receive light stimulus from the external environment and send it to retinal ganglionic cells (RGC), one of the cell types of which the retina is composed. The retina, the internal visual membrane of the eye, processes the visual stimuli in electric stimuli to transfer it to the brain, through the optic nerve. Retinal chronic progressive neurodegeneration, which may occur among the elderly, can lead to different disorders of the eye such as glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR). Mainly in the elderly population, but also among younger people, such ocular pathologies are the cause of irreversible blindness or impaired, reduced vision. Typical neurodegenerative diseases of the CSN are a group of pathologies with common characteristics and etiology not fully understood; some risk factors have been identified, but they are not enough to justify all the cases observed. Furthermore, several studies have shown that also ocular disorders present characteristics of neurodegenerative diseases and, on the other hand, CNS pathologies, i.e., Alzheimer disease (AD) and Parkinson disease (PD), which are causes of morbidity and mortality worldwide, show peculiar alterations at the ocular level. The knowledge of possible correlations could help to understand the mechanisms of onset. Moreover, the underlying mechanisms of these heterogeneous disorders are still debated. This review discusses the characteristics of the ocular illnesses, focusing on the relationship between the eye and the brain. A better comprehension could help in future new therapies, thus reducing or avoiding loss of vision and improve quality of life.

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