Comparison of pancreas-transplanted type 1 diabetic patients with portal-venous versus systemic-venous graft drainage: impact on glucose regulatory hormones and the growth hormone/insulin-like growth factor-I axis.
BACKGROUND
Pancreas grafts can be drained through the iliac vein (systemic drainage) or the portal vein.


OBJECTIVE
We hypothesized that normalization of portal insulin in patients with portal pancreas graft drainage stimulates the GH/IGF-I axis and thereby contributes to glucose control.


METHODS
We compared patients after combined kidney and pancreas transplantation with portal drainage (n = 7) to patients with systemic drainage of the pancreas graft (n = 8) and nondiabetic controls (n = 8). Overnight fasting sera were analyzed for free and total IGF-I and IGF-binding proteins. Glucose regulatory hormones were examined after an oral glucose tolerance test and GH after stimulation with GHRH.


RESULTS
Systemic drainage led to higher basal and stimulated insulin levels than portal drainage (P < 0.05), but increments in response to oral glucose were reduced in both transplanted groups (P < 0.05 vs. controls). However, glucose tolerance was similar in all groups. Circulating free and total IGF-I and IGF-binding protein-3 were similar to control levels in the systemic drainage group but elevated in the portal drainage group (P < 0.05). Consistently, the GH response was reduced in the portal drainage group (P < 0.05 vs. controls) and correlated inversely with free IGF-I (r = -0.63, P < 0.05).


CONCLUSIONS
Portal drainage of pancreatic endocrine secretion in pancreas graft recipients raises IGF-I and lowers GH secretion. These changes might explain that glucose regulation is maintained despite lower peripheral insulin levels, compared with patients with systemic graft drainage and nondiabetic control subjects.
Frystyk
Jan
J
Medical Research Laboratories, Aarhus University Hospital, Nørrebrogade 44, Aarhus C, Denmark. jan@frystyk.dk
Ritzel
Robert A
RA
Maubach
J
J
Büsing
Martin
M
Lück
Rainer
R
Klempnauer
Jürgen
J
Schmiegel
Wolff
W
Nauck
Michael A
MA
D000328:Adult; D002096:C-Peptide / Q000032:analysis; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology / Q000601:surgery*; D004322:Drainage; D005260:Female; D005934:Glucagon / Q000097:blood; D005951:Glucose Tolerance Test; D019382:Human Growth Hormone / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007328:Insulin / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D016035:Pancreas Transplantation; D011169:Portal Vein / Q000502:physiology
D002096:C-Peptide; D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D005934:Glucagon