Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 166 (1976), S. 521-530 
    ISSN: 1432-0878
    Keywords: Ependyma ; Fish ; Third ventricle ; Hypothalamus ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ependyma lining the lateral recess of the third ventricle of the teleost inferior lobe has been studied by light and electron microscopy, including Golgi impregnation methods. As many as five different cell types appear to line the ventricle, but some of these may be similar cells in different stages of activity. One cell type contains small dense-cored vesicles and appears to have processes extending into deeper portions of the lobe. Golgi preparations reveal subependymal cells with apical processes extending to the ventricle and basal extensions which may reach the pial surface. The present observations are discussed in relation to similar studies in other fishes, amphibians and mammals. Possible functions for the various cells observed are suggested.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Neurochemical research 9 (1984), S. 207-217 
    ISSN: 1573-6903
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The long-acting opiate antagonist naltrexone hydrochloride was administered by intraperitoneal injection, in a dose response protocol, to adult rats. The drug was used to observe effects of opiate receptor blockade on cells of the pituitary gland and adjacent hypothalamus. At higher drug doses (5mg/kg or 10mg/kg), neurites directly innervating pars intermedia cells contained swollen vesicles and disrupted membranous elements. Fibers within the median eminence of the hypothalamus appeared swollen, and contained myelin figures. Despite the consistent degenerative changes appearing in neurites, measurements of levels of dopamine, norepinephrine, and epinephrine in striatum, and hypothalamus did not differ significantly between naltrexone-treated or control animals, although there was a significant elevation of norepinephrine in the pituitary after drug treatment. At all drug dose levels administered, supraependymal neuron-like cells appeared atop the ependyma of the third ventricle above the median eminence. These observations suggest that naltrexone produces specific “neurotoxic” effects on neurites of the tuberoinfundibular system, and may induce changes in the ventricular environment which stimulate the appearance of supraependymal neurons.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-0878
    Keywords: Opiate peptides ; Pituitary ; Pro-opiomelanocortin cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of acute injections of synthetic opiate peptides into the lateral cerebral ventricle of young adult male rats on cells of the intermediate lobe of the pituitary were studied. Met-enkephalin (100/μg) injected into anesthetized rats, or 20 μg beta-endorphin administered via a previously implanted cannula to unanesthetized animals, will lead to cell degranulation and often to expanded Golgi zones and prominent regions of rough endoplasmic reticulum in secretory cells when tissue is fixed 45–60 min after peptide administration. Treatment of animals with the opiate antagonist naloxone hydrochloride prior to enkephalin injection appeared to prevent the cellular changes elicited with peptide alone. Observations suggest that opiate peptides administered to the cerebrospinal fluid may stimulate release of pro-opiomelanocortin-peptide from pituitary cells.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 194 (1978), S. 115-123 
    ISSN: 1432-0878
    Keywords: Pars intermedia ; Fine structure ; Reserpine ; Freeze fracture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hormone release from the pars intermedia is under inhibitory control of the hypothalamus. Control may be mediated via dopaminergic fibers which directly contact secretory cells. Administration of reserpine in vivo to adult male rats for four consecutive days results in major alternations in pars intermedia cytology. Cells show expanded areas and whorls of rough endoplasmic reticulum, as well as extensive Golgi zones with numerous dense granules. Some nerve fibers exhibit alterations in vesicle content, while others retain a more normal appearance. Freeze-fracture of glands from reserpine-treated animals provides evidence for exocytosis of granules, although such phenomena are not observed in thin sections. The ultrastructural findings suggest that reserpine alters the content of local inhibitory neurotransmitters in the pars intermedia, leading to unrestrained hormone release, followed by renewed granule synthesis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 187 (1977), S. 207-217 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Mice fed a high cholesterol-cholic acid diet for two to six months develop gallstones; these were studied by transmission electron microscopy after glutaraldehyde-digitonin fixation. Examination of the contents of mouse gallbladders presents views of layered structures and surrounding amorphous material. We interpret these images of gallstones to suggest that they may arise by cohesion of material rich in cholesterol to form more ordered structures. Gallbladder contents of mice fed the diet for five to six months were found to contain occasional crystals and rectangular areas similar to those observed in thin sections of human gallstones (unpublished observations). Recent findings that human gallstones can be dissolved with chenodeoxycholic acid are discussed, with reference to their applicability to studies of gallstones in mice.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 657-665 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ultrastructure of ependymal cells of the median eminence in young Pacific blacktip reef sharks is described. Three major cell types have been observed. The first type is an irregularly-shaped, electron dense cell with many long microvilli and occasional cilia projecting into the ventricle. A second type contains dense cytoplasmic granules in sizes ranging from 1000-2000 Å, and may be morphologically equivalent to “liquor-contacting neurons” observed in ependymal linings elsewhere. The third type appears very similar to crown cells of saccus vasculosus of this and other species. Cells of the third type possess large, lipid-like inclusions, bulbous projections originating from basal bodies, and prominent smooth endoplasmic reticulum. The crown-like cells are compared to cells of saccus vasculosus of young and adult sharks, and their possible significance is discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 200 (1981), S. 315-319 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Small numbers of dividing cells were observed in the pituitary intermediate lobe of normal and p-chloroamphetamine-treated adult male rats. Ultrastructural examination reveals that the mitotic elements are granulated MSH/endorphin cells. Nerve fibers providing direct innervation could be found on dividing cells. The observations illustrate a limited potential for proliferation in the adult MSH/endorphin cell population.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 194 (1979), S. 113-123 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Mice fed a high cholesterol-cholic acid (lithogenic) diet for one year develop fatty livers in addition to gallstones. Light and electron micrographs demonstrate large amounts of lipids in liver parenchymal cells, often to the exclusion of most other cytoplasmic organelles. In addition, some hepatocytes exhibit nuclear lipid pseudo- and true inclusions. Other prominent features of hepatocytes after lithogenic diet include segregation of nucleolar granular and fibrillar material. Accumulation of considerable collagen in extracellular spaces is also noted. Observations suggest changes induced by the cholesterol diet are comparable to cytologic alterations seen in spontaneous and drug induced hepatic tumors, as well as to more general “fatty metamorphosis” of the liver.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 210 (1984), S. 115-123 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Beta-endorphin-related opiate peptides or the opiate antagonist naloxone were chronically infused for periods of 24 to 48 hours to the lateral cerebral ventricle of adult male rats using Alza osmotic minipumps. Previous studies have suggested a “chemotactic”-like effect of opiate peptides for supraependymal macrophages in the region of the third ventricle of the brain. The present study demonstrates a stimulatory effect of beta-endorphin infusion on the appearance of lymphocyte and neutrophil-like cells, in addition to macrophages, in the region of the third ventricle, suggestive of an intracerebral inflammatory response. None of the other molecules, including alphaendorphin, methionine-enkephalin, naloxone, or sterile saline produced similar cellular responses after infusion, although some of the latter substances may have induced the appearance of supraependymal neuron-like cells in the area. Observations suggest that the chronic presence of beta-endorphin, a biologically active opiate peptide, will interact with cells of the immune system, which have the ability to gain access to the cerebrospinal fluid.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 174 (1972), S. 157-164 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Tritiated digitonin of high specific activity has been incorporated into fixation of adult rat sciatic nerve. Electron microscope autoradiograms developed four to thirteen days after coating indicate highest concentration of label over or near myelin sheaths. Label is observed over areas of reasonable myelin preservation as well as in areas of artifact and membrane disruption. The technique is suggested for use as a means of fairly specific localization of free cholesterol in tissues. In addition, the activity of the isotope used permits visualization of autoradiograms after short exposure times.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...