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.

Context: 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-bindin...