Glucagon production of the rat insulinoma cell line INS-1-A quantitative comparison with primary rat pancreatic islets.
The rat insulinoma cell line INS-1 is the most commonly used clonal cell model in pancreatic beta-cell research. Considering the multihormonality of many insulinomas we examined as to how INS-1 cells comply with the notion of resembling a pure beta-cell line. Glucagon immunoassays revealed that INS-1 cells secrete glucagon in a similar range as islets. By immunohistochemistry we detected a cytoplasmic glucagon signal in INS-1 cells which colocalized with C-peptide. Cellular content of preproglucagon-mRNA and glucagon protein in INS-1 cells was less than two percent of the respective values in islets, which probably reflects differences in the intracellular metabolism and/or secretory pathways. Taken together, it is obvious that INS-1 cells do not represent an exclusively insulin producing beta-cell line.
Bollheimer
L Cornelius
LC
Department of Internal Medicine I, University of Regensburg, 93042 Regensburg, Germany. cornelius.bollheimer@klinik.uni-regensburg.de <cornelius.bollheimer@klinik.uni-regensburg.de>
Wrede
Christian E
CE
Rockmann
Felix
F
Ottinger
Iris
I
Schölmerich
Jürgen
J
Buettner
Roland
R
D000818:Animals; D045744:Cell Line, Tumor; D005934:Glucagon / Q000096:biosynthesis*; D007340:Insulinoma / Q000378:metabolism*; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D019308:Palmitic Acid / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats
D012333:RNA, Messenger; D019308:Palmitic Acid; D005934:Glucagon