Antral G-cell in gastrin and gastrin-cholecystokinin knockout animals.
The antral hormone gastrin is the key regulator of gastric acid secretion, mucosal growth and differentiation. Gastrin is synthesized in the endocrine G-cells in the antroduodenal mucosa. We have now examined the way in which the loss of gastrin alone or gastrin plus cholecystokinin (CCK) affects the antral G-cell. Immunohistochemistry, radioimmunoassay and quantitative real-time polymerase chain reaction techniques were employed to examine the expression of genes belonging to the G-cell secretory pathway in gastrin and gastrin-CCK knockout mice. Transmission electron microscopy was used to examine the ultrastructure of the G-cells. The number of G-cells increased but the secretory granules were few and abnormally small in the G-cells of both mouse models compared with wildtypes. Thus, gastrin is not necessary for the formation of G-cells as such but the lack of gastrin reduces the number and size of their secretory granules suggesting that gastrin is vital for the formation and/or maintenance of secretory granules in G-cells.
Friis-Hansen
Lennart
L
Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. lfh@rh.dk
Wierup
Nils
N
Rehfeld
Jens F
JF
Sundler
Frank
F
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002766:Cholecystokinin / Q000032:analysis / Q000235:genetics*; D053379:Chromogranin A; D002864:Chromogranins / Q000378:metabolism; D005753:Gastric Mucosa / Q000166:cytology* / Q000378:metabolism; D019863:Gastrin-Secreting Cells / Q000378:metabolism* / Q000648:ultrastructure; D005755:Gastrins / Q000032:analysis / Q000235:genetics*; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D051379:Mice; D008822:Mice, Transgenic; D008854:Microscopy, Electron; D045664:Proprotein Convertase 1 / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011863:Radioimmunoassay; D020133:Reverse Transcriptase Polymerase Chain Reaction
D015415:Biomarkers; D053379:Chromogranin A; D002864:Chromogranins; D005755:Gastrins; D012333:RNA, Messenger; D002766:Cholecystokinin; D045664:Proprotein Convertase 1