Journal of Histochemistry and Cytochemistry Priciples for Free Access to Science
  Search:   
    >> Advanced Search

Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Grondin, G.
Right arrow Articles by LeBel, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Grondin, G.
Right arrow Articles by LeBel, D.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
Journal of Histochemistry and Cytochemistry, Vol. 47, 489-498, April 1999, Copyright © 1999, The Histochemical Society, Inc.

ARTICLE

Specific Localization of Membrane Dipeptidase and Dipeptidyl Peptidase IV in Secretion Granules of Two Different Pancreatic Islet Cells

Gilles Grondina, Nigel M. Hooperb, and Denis LeBela
a Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec, Canada
b School of Biochemistry and Molecular Biology, University of Leeds, Leeds, United Kingdom

Correspondence to: Denis LeBel, Dept. of Biology, University of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1.

Endocrine cells require several protein convertases to process the precursors of hormonal peptides that they secrete. In addition to the convertases, which have a crucial role in the maturation of prohormones, many other proteases are present in endocrine cells, the roles of which are less well established. Two of these proteases, dipeptidyl peptidase IV (EC 3.4.14.5) and membrane dipeptidase (EC 3.4.13.19), have been immunocytochemically localized in the endocrine pancreas of the pig. Membrane dipeptidase was present exclusively in cells of the islet of Langerhans that were positive for the pancreatic polypeptide, whereas dipeptidyl peptidase IV was restricted to cells positive for glucagon. Both enzymes were observed in the content of secretory granules and therefore would be released into the interstitial space as the granules undergo exocytosis. At this location they could act on secretions of other islet cells. The relative concentration of dipeptidyl peptidase IV was lower in dense glucagon granules, where the immunoreactivity to glucagon was higher, and vice versa for light granules. This suggests that, in A-cells, dipeptidyl peptidase IV could be sent for degradation in the endosomal/lysosomal compartment during the process of granule maturation or could be removed from granules for continuous release into the interstitial space. The intense proteolytic activity that takes place in the endocrine pancreas could produce many potential dipeptide substrates for membrane dipeptidase. (J Histochem Cytochem 47:489–497, 1999)

Key Words: endocrine pancreas, dipeptidyl peptidase IV, membrane dipeptidase, {alpha}-cells, PP cells, secretion granule, glucagon, pancreatic polypeptide


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:


Home page
 J. Biol. Chem.Home page
S. A. Hinke, J. A. Pospisilik, H.-U. Demuth, S. Mannhart, K. Kuhn-Wache, T. Hoffmann, E. Nishimura, R. A. Pederson, and C. H. S. McIntosh
Dipeptidyl Peptidase IV (DPIV/CD26) Degradation of Glucagon. CHARACTERIZATION OF GLUCAGON DEGRADATION PRODUCTS AND DPIV-RESISTANT ANALOGS
J. Biol. Chem., February 11, 2000; 275(6): 3827 - 3834.
[Abstract] [Full Text] [PDF]



Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact
The Journal of Histochemistry & Cytochemistry is owned, published, and licensed by The Histochemical Society © 1999

 
Purchase HCS Short Course Manual on HCS site