Glucagon levels and ketogenesis in human diabetes following total or partial pancreatectomy and severe chronic pancreatitis

Summary In three groups of patients with insulin-dependent diabetes following total (n=5) or partial (n=5) pancreatectomy or chronic pancreatitis (n=7) and in a group of idiopathic diabetics, ketogenic capacity following insulin withdrawal and during a 24-h fast was studied. Basal glucagon values were significantly increased in all diabetic groups with no significant intergroup differences. Basal ketone body values and their increase during starvation and insulin withdrawal were high and not different in totally pancreatectomized and primary diabetics, both showing unmeasurable C-peptide levels. On the contrary, ketogenesis was reduced in partially pancreatectomized and in pancreatitis diabetics with persistent levels of C-peptide. Our data confirmed the persistence of immunoreactive glucagon after pancreatectomy and demonstrated that ketogenesis is not suppressed in pancreatectomized diabetics and depends above all on residual B-cell function. A possible ketogenic effect of extra-pancreatic glucagon-like substances cannot be excluded.