C-peptide constricts pancreatic islet arterioles in diabetic, but not normoglycaemic mice.
BACKGROUND
Pancreatic islet blood flow is regulated separately from that of the exocrine pancreas, and a consistent finding during impaired glucose tolerance is an increased blood perfusion. The aim of the present study was to investigate whether C-peptide affects pancreatic islet arterioles in normal and diabetic mice.


METHODS
Control and diabetic C57-Bl mice were studied after 2 weeks of alloxan-induced diabetes. Islet arterioles were dissected and microperfused with Dulbecco's modified Eagle medium (DMEM) solution. The effect of luminal application of mouse C-peptide was investigated.


RESULTS
C-peptide reduced the diameter of islet arterioles from diabetic mice (-10+/-4%, P<0.05) compared to base-line values, whilst arterioles from normoglycaemic animals did not respond to C-peptide (P=0.2).


CONCLUSIONS
These findings suggest a role for C-peptide in the regulation of islet blood flow, especially during conditions with impaired glucose tolerance.
D000818:Animals; D001160:Arterioles / Q000187:drug effects*; D002096:C-Peptide / Q000494:pharmacology*; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D007515:Islets of Langerhans / Q000098:blood supply*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012039:Regional Blood Flow / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects*
D002096:C-Peptide