Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Electronic Resource  (2)
  • Endocrine pancreas  (1)
  • Islets of Langerhans  (1)
  • 1
    Electronic Resource
    Electronic Resource
    The microanatomy of canine islets of Langerhans: implications for intra-islet regulation (1992)
    Springer
    Anatomy and embryology 185 (1992), S. 131-141 
    Details
    ISSN: 1432-0568
    Keywords: Dogs ; Islets of Langerhans ; Extrainsular endocrine cells ; Immunohistochemistry ; Regulation of islets
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In recent years models for the internal (“intra-islet”) regulation of hormone secretion have been proposed to explain how different islet cells might regulate each other by means of their respective secretory peptides. Models that emphasize the importance of a directed intra-islet blood flow and sequence of perfusion of islet cells rely on a certain type of islet microanatomy and vascular supply. The experimental studies underlying these models have partly been performed in dogs. To extend the incomplete morphological knowledge of the canine endocrine pancreas both canine islets of Langerhans and extrainsular cells have been analysed in immunostained serial semithin (0.5 μm) sections. In addition to their occurrence within islets of Langerhans, all endocrine cell types are also found at extrainsular sites (about 9% of all endocrine cells) where they are distributed in different quantities among the epithelial lining of exocrine acini or excretory ducts and the connective tissue. There are continuous transitions from single extrainsular cells to small mono-and polycellular cell groups to islets. In a comprehensive analysis of whole islets, including computer-assisted three-dimensional reconstructions, the size, shape and vascularization of the islets as well as their cellular composition and the microtopology of islet cells have been studied. We have found marked intra-and inter-islet heterogeneities of the parameters investigated that are not compatible with concepts of a uniform and directed vascular perfusion of the various islet cell populations. Instead, their paracrine regulation may occur primarily via hormonal secretion into the intercellular spaces or vascular hormonal delivery to adjacent cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00185914
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Synaptophysin immunoreactivity in the mammalian endocrine pancreas (1991)
    Springer
    Cell & tissue research 264 (1991), S. 461-467 
    Details
    ISSN: 1432-0878
    Keywords: Synaptophysin ; P38 ; Membrane proteins ; Endocrine pancreas ; Islet cells ; Immunohistochemistry ; Human ; Dog ; Gerbil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Synaptophysin, a major membrane glycoprotein of small presynaptic vesicles in neurons, has also been found in microvesicles of endocrine cells, e.g., of the endocrine pancreas. In the present study, the endocrine pancreas in 9 mammalian species (man, dog, mink, bovine, rabbit, guinea pig, rat, mouse, gerbil) has been investigated immunohistochemically for synaptophysin immunoreactivity. Synaptophysin-positive cells have been identified and localized on semithin plastic sections. Our study demonstrates that, in all species examined, all pancreatic endocrine cell types are consistently synaptophysin-positive independent of their location within the tissue, or the conditions of tissue processing. In addition, a few cells that cannot be hormonally identified show synaptophysin immunoreactivity. Hence, synaptophysin appears to be a regular constituent of all pancreatic endocrine cells in mammals. In several species, a subpopulation of endocrine cells, consisting of glucagon-containing and/or pancreatic-polypeptide-containing cells, exhibits a significantly higher degree of synaptophysin immunoreactivity. In the gerbil, this heterogeneity can readily be detected from the day of birth onwards. Our findings indicate that closely related endocrine cell types may differ with respect to the content of synaptophysin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00319036
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...