scholarly journals FIXATION OF NEURAL TISSUES FOR ELECTRON MICROSCOPY BY PERFUSION WITH SOLUTIONS OF OSMIUM TETROXIDE

1962 ◽  
Vol 12 (2) ◽  
pp. 385-410 ◽  
Author(s):  
Sanford L. Palay ◽  
S. M. McGee-Russell ◽  
Spencer Gordon ◽  
Mary A. Grillo
Keyword(s):  
Electron Microscopy ◽  
Nervous System ◽  
Osmium Tetroxide ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
Vascular Perfusion ◽  
Neural Tissues ◽  
Structural Relations ◽  
Cellular Components

This paper describes in detail a method for obtaining nearly uniform fixation of the nervous system by vascular perfusion with solutions of osmium tetroxide. Criteria are given for evaluating the degree of success achieved in the preservation of all the cellular components of the nervous system. The method permits analysis of the structural relations between cells at the electron microscopic level to an extent that has not been possible heretofore.

A combined pre- and post-embedding double labeling in the central nervous system with good tissue preservation

1991 ◽  
Vol 49 ◽  
pp. 276-277
Author(s):  
A.M. Milroy ◽  
D.D. Ralston
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
Double Labeling ◽  
Highly Sensitive ◽  
The Central Nervous System

Multiple labeling at the electron microscopic level is routinely done in various parts of the central nervous system. We demonstrate that the pre-embedding tetramethylbenzidine (TMB) reaction for visualizing horseradish peroxidase (HRP) of Olucha and the slow osmication of Henry combined with a post-embedding nonetching immunogold method will also preserve good ultrastructure. Furthermore, the post-embedding immunocytochemistry of some neurotransmitters, i.e. gammaaminobutyric acid (GABA), can be done months after the tissue has been reacted for HRP and embedded in regular epon.Pre-embedding histochemistry:The use of TMB as a chromagen for the demonstration of neuronally transported HRP has both the advantage of being highly sensitive and of producing very specific needle-like crystals. Olucha et al demonstrated that one could further stabilize this reaction product with amonium heptamolybdate. Unfortunately the next step, fixation with regular osmium tetroxide, often resulted in the loss of the reaction product. However, the slow osmication with a lower pH (5.5) in the phosphate buffer at room temperature as recommended by Henry et al prevented this loss, and at the same time resulted in well preserved ultrastructure.

X-Ray Microanalysis of Nickel and Cobalt Intensified Peroxidase- Antiperoxidase For Verification of Reaction Sites

1985 ◽  
Vol 43 ◽  
pp. 468-469
Author(s):  
A. Angel ◽  
K. Miller ◽  
V. Seybold ◽  
R. Kriebel
Keyword(s):  
Reaction Mechanisms ◽  
Visual Discrimination ◽  
Osmium Tetroxide ◽  
Ultrastructural Level ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
X Ray ◽  
Insoluble Polymer ◽  
Cytochemical Reaction

Localization of specific substances at the ultrastructural level is dependent on the introduction of chemicals which will complex and impart an electron density at specific reaction sites. Peroxidase-antiperoxidase(PAP) methods have been successfully applied at the electron microscopic level. The PAP complex is localized by addition of its substrate, hydrogen peroxide and an electron donor, usually diaminobenzidine(DAB). On oxidation, DAB forms an insoluble polymer which is able to chelate with osmium tetroxide becoming electron dense. Since verification of reactivity is visual, discrimination of reaction product from osmiophillic structures may be difficult. Recently, x-ray microanalysis has been applied to examine cytochemical reaction precipitates, their distribution in tissues, and to study cytochemical reaction mechanisms. For example, immunoreactive sites labelled with gold have been ascertained by means of x-ray microanalysis.

scholarly journals Analytical electron microscopic evaluation of the effects of paraformaldehyde pretreatment on the reaction of glutaraldehyde with biogenic amines.

1982 ◽  
Vol 30 (5) ◽  
pp. 481-486 ◽  
Author(s):  
R E McClung ◽  
J Wood
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Spectrographic Analysis ◽  
Electron Microscopic ◽  
X Ray ◽  
Microscopic Evaluation ◽  
Analytical Electron ◽  
Dense Product

Analytical electron microscopy was used to determine the quantitative effects of paraformaldehyde pretreatment on the formation of the biogenic amine-glutaraldehyde-chrome complex. Pretreatment with paraformaldehyde prevented the glutaraldehyde-chrome reaction with norepinephrine in the rat adrenal medulla. In contrast to the effect of paraformaldehyde on norepinephrine, pretreatment did not prevent the chrome reaction in serotonin-containing argentaffin cells of the gut. X-Ray energy spectrographic analysis revealed a significant decrease in chrome content in the paraformaldehyde treated tissue, but sufficient chrome did react to produce an electron-dense product. Thus by treating tissue with paraformaldehyde prior to the glutaraldehyde chrome procedure, serotonergic sites may be differentiated from catecholaminergic areas at the electron microscopic level.

Electron microscopy of changes in lower extremity muscles in Duchenne muscular dystrophy

1991 ◽  
Vol 81 (6) ◽  
pp. 294-299
Author(s):  
J Atkin ◽  
VW Thompson ◽  
RB Boyd
Keyword(s):  
Electron Microscopy ◽  
Duchenne Muscular Dystrophy ◽  
Muscular Dystrophy ◽  
Genetic Disease ◽  
Extensor Digitorum Longus ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
Dystrophic Mice ◽  
Insight Into

Duchenne muscular dystrophy is a genetic disease with a sex-linked pattern of inheritance. This disease is present at birth, becomes symptomatic during early childhood, leads to inability to walk near the end of the first decade, and usually results in death by the end of the second decade. In this study, the extensor digitorum longus and soleus muscles from genetically dystrophic mice were examined at the electron microscopic level. The authors describe their results and discuss how these findings might provide some insight into one of the mechanisms of fiber necrosis in Duchenne muscular dystrophy.

Techniques Involved in the Acquisition of Serial Sections of the Atrioventricular Node for Light and Electron Microscopy

1968 ◽  
Vol 26 ◽  
pp. 226-227
Author(s):  
Sheila S. Emmett ◽  
J. C. Thaemert
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Light And Electron Microscopy ◽  
Atrioventricular Node ◽  
Electron Microscopic Level ◽  
Serial Sections ◽  
Electron Microscopic ◽  
Trapezoidal Shape ◽  
Old Mice

The acquisition of serial sections of the atrioventricular node for light and electron microscopy is a formidable task. Ordinary techniques are not adequate if the best possible results are to be achieved at the electron microscopic level. The techniques outlined below have proven to be valuable in locating and determining the position of the AV node.Whole hearts of 2-week old mice were fixed, in situ, by perfusion with 1% phosphate-buffered osmium tetroxide. The hearts were removed from the animals, sectioned transversely into 3 slices approximately equal in thickness, dehydrated in graded concentrations of ethanol and embedded in Epon 812. The block faces were trimmed to a trapezoidal shape ranging in size from 0.75 x 1 mm to 4 x 5 mm. Serial sections approximately 2 microns in thickness were cut with glass knives on a Porter-Blum MT-2 Ultramicrotome. While floating on a drop of water on the knife, each section was stretched with 1 drop of a 1:1, xylene in chloroform mixture applied directly to the section. The sections were picked up individually with a brush, transferred to a glass slide and oven dried for several hours prior to staining.

scholarly journals Photoconversion and electron microscopic localization of the fluorescent axon tracer fluoro-ruby (rhodamine-dextran-amine).

1993 ◽  
Vol 41 (5) ◽  
pp. 777-782 ◽  
Author(s):  
L C Schmued ◽  
L F Snavely
Keyword(s):  
Electron Microscopy ◽  
Green Light ◽  
Microscopic Level ◽  
Synaptic Connectivity ◽  
Electron Microscopic Level ◽  
Light Microscopic Level ◽  
Electron Microscopic ◽  
Axon Transport ◽  
Conventional Electron Microscopy ◽  
Electron Microscopic Localization

Fluoro-Ruby, the fluorescent tetramethylrhodamine-dextran-amine used to demonstrate anterograde axon transport, has been successfully photoconverted and subsequently localized by electron microscopy. The photoconversion was accomplished by irradiating the tissue with green light while bathing it in a solution containing DAB. The tissue could then be examined by brightfield microscopy or processed for conventional electron microscopy. Potential advantages of the technique include greater permanence and contrast at the light microscopic level and the ability to resolve synaptic connectivity at the electron microscopic level.

scholarly journals Morphological Signs of Dystrophy, Regeneration and Hypertrophy of Neurons

2021 ◽  
pp. 1-6
Author(s):  
Bon EI ◽  
◽  
Malykhina AV ◽  
Keyword(s):  
Nervous System ◽  
Nerve Cell ◽  
Pathological Process ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
Olfactory Bulbs ◽  
Intracellular Regeneration ◽  
Lateral Ventricles ◽  
Neuronal Disorders

Results: Dystrophic changes constitute an extensive group of neuronal disorders and are manifested at the morphological level by deformation of the perikarions and neuropil, wrinkling or swelling of the cell, and changes in the chromatophilia of the cytoplasm. At the electron microscopic level, disorganization of organelles is observed, reflecting gross violations of the vital processes of the neuron. There are several ways to regenerate neurons: intracellular regeneration, restoration of the neuropil, the formation of new neurons (in some parts of the nervous system - the hippocampus, the subventricular layer of the lateral ventricles and olfactory bulbs) and the formation of heterokaryons (fusion of a neuron with an oligodendrocyte). Hypertrophy of neurons may indicate both compensation and the development of a pathological process. To clarify the nature of this phenomenon, it is necessary to conduct an ultramicroscopic study of the organelles of the nerve cell.

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