Angiotensinogen localization and secretion in the rat pancreas

in Journal of Endocrinology
Authors:
M Regoli
Search for other papers by M Regoli in
Current site
Google Scholar
PubMed
Close
,
M Bendayan
Search for other papers by M Bendayan in
Current site
Google Scholar
PubMed
Close
,
L Fonzi
Search for other papers by L Fonzi in
Current site
Google Scholar
PubMed
Close
,
C Sernia
Search for other papers by C Sernia in
Current site
Google Scholar
PubMed
Close
, and
E Bertelli
Search for other papers by E Bertelli in
Current site
Google Scholar
PubMed
Close
View More View Less
Free access

Renin and angiotensinogen have been previously found in the rat pancreas, and angiotensin receptors have been located in the apical domain of duct cells. To evaluate the possibility that angiotensin II could be generated within the duct system, we decided to determine whether angiotensinogen is present in rat pancreatic juice and the angiotensinogen-immunoreactive pancreatic cell types that could be responsible for its production. Angiotensinogen was detected in significant amounts by Western blotting in pancreatic juice collected from several individual rats. Different isoforms between plasma and pancreatic juice angiotensinogens were demonstrated by isoelectric focusing. Immunocytochemical experiments revealed angiotensinogen-immunoreactive cells at the periphery of the islets of Langerhans, and confocal microscopy demonstrated that most angiotensinogen-immunoreactive cells were glucagon-secreting cells. Secretion of angiotensinogen did not follow the regulated secretory pathway since it was absent from the glucagon-containing granules. This was confirmed by electron microscopy immunocytochemistry. Duct and acinar cells did not express angiotensinogen at an immunocytochemical detectable level. The present findings indicated an exocrine secretion of angiotensinogen by glucagon-secreting cells and suggest that one of the final targets of the local pancreatic renin-angiotensin system may be the duct epithelium.

 

  • Collapse
  • Expand