title: Insulin and C-peptide plasma levels in patients with severe chronic pancreatitis and fasting normoglycemia.
abstract: The aim of the present study was to evaluate insulin secretion by the pancreatic B cell in a group of patients with severe chronic pancreatitis and without overt diabetes. For this purpose we have measured plasma insulin and C-peptide peripheral levels in the fasting state and after a 100-g oral glucose load in 10 patients with severe chronic pancreatitis and fasting normoglycemia, and in 10 sex-, age-, and weight-matched healthy controls. As compared to normal subjects, patients with chronic pancreatitis showed: (1) significantly higher plasma glucose levels after oral glucose load (area under the plasma glucose curve 1708 +/- 142 vs 1208 +/- 47 mmol/liter X 240 min, P less than 0.005); (2) plasma insulin levels significantly higher at fasting (0.11 +/- 0.008 vs 0.08 +/- 0.005 nmol/liter, P less than 0.01) but not after oral glucose administration (area under the plasma insulin curve 79 +/- 12 vs 88 +/- 16 nmol/liter X 240 min); (3) significantly lower plasma C-peptide concentrations both in the fasting state (0.15 +/- 0.01 vs 0.54 +/- 0.05 nmol/liter, P less than 0.001) and after oral glucose load (area under the plasma C-peptide curve 211 +/- 30 vs 325 +/- 37 nmol/liter X 240 min, P less than 0.05). The finding of diminished plasma C-peptide levels suggests that chronic pancreatitis is associated with an impaired B-cell function even in the absence of overt diabetes. The increased or unchanged plasma insulin levels in spite of decreased plasma C-peptide concentrations indicate that in chronic pancreatitis insulin metabolism is reduced, most likely within the liver.
authors.affiliation: Institute of Clinica Medica Generale, Parma University Medical School, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Bonora
authors.forename: C
authors.initials: C
authors.lastname: Rizzi
authors.forename: C
authors.initials: C
authors.lastname: Lesi
authors.forename: P
authors.initials: P
authors.lastname: Berra
authors.forename: C
authors.initials: C
authors.lastname: Coscelli
authors.forename: U
authors.initials: U
authors.lastname: Butturini
mesh_terms: D001786:Blood Glucose / Q000032:analysis*; D002096:C-Peptide / Q000097:blood*; D002908:Chronic Disease; D005215:Fasting; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood* / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism; D010195:Pancreatitis / Q000097:blood*; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin