Splanchnic metabolism of alanine in intact man. Effects of somatostatin and somatostatin plus insulin.
We examined splanchnic metabolism of alanine in 15 normal males under three sets of conditions: infusion of saline (control studies); infusion of somatostatin (SRIF) (bihormonal deficiency of insulin and glucagon); and infusion of somatostatin plus insulin (selective glucagon deficiency). Net splanchnic alanine uptake (NSAU) remained stable over 2 h during infusion of saline. Infusion of SRIF was associated with a fall in estimated hepatic plasma flow (EHPF) whether or not insulin was infused concomitantly. With SRIF only, arterio-hepatic venous alanine differences increased such that NSAU remained stable over 2 h, despite the fall in EHPF. In contrast, with selective glucagon deficiency, NSAU fell significantly after 2 h, an effect consequent on a fall in EHPF and a delayed fall in arterio-hepatic venous (A-HV) alanine differences. Our studies are compatible with a role for basal glucagon in maintenance of splanchnic extraction of alanine in normal man. However, the SRIF-initiated fall in EHPF may exert an influence on A-HV alanine differences independent of changes in pancreatic hormone secretion.
D000328:Adult; D000409:Alanine / Q000097:blood*; D001786:Blood Glucose / Q000378:metabolism; D004064:Digestive System / Q000378:metabolism; D005934:Glucagon / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D008102:Liver Circulation; D008297:Male; D012039:Regional Blood Flow; D013004:Somatostatin
D001786:Blood Glucose; D007328:Insulin; D013004:Somatostatin; D005934:Glucagon; D000409:Alanine