Basal and tolbutamide-induced plasma somatostatin in healthy subjects and in patients with diabetes and impaired glucose tolerance.
Peripheral levels of basal and tolbutamide-induced somatostatin have been measured in patients with diabetes or impaired glucose tolerance (IGT) and compared with those in normal individuals. Basal somatostatin was significantly higher in patients with Type 1 diabetes than in age-matched control subjects. This increase was most pronounced at diagnosis, and appeared to be related to metabolic control in insulin-treated patients. No increase was noted in patients with Type 2 diabetes or with IGT. Intravenous bolus injection of tolbutamide enhanced peripheral somatostatin levels in healthy volunteers in a biphasic manner. Patients with IGT also exhibited a biphasic response but the amplitude of the first phase was higher. No secretory response was detected in 27/29 Type 1 diabetic patients at diagnosis; a somatostatin response to tolbutamide became detectable again in Type 1 patients with normalization of their basal somatostatin levels but was then paradoxically related to poor blood glucose control. In Type 2 diabetes, basal somatostatin levels were similar to age-matched control subjects, but decreased upon intravenous tolbutamide administration.
Segers
O
O
Department of Metabolism and Endocrinology, Vrije Universiteit Brussel, Belgium.
De Vroede
M
M
Michotte
Y
Y
Somers
G
G
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D008875:Middle Aged; D013004:Somatostatin / Q000097:blood*; D014044:Tolbutamide / Q000008:administration & dosage / Q000494:pharmacology*
D001786:Blood Glucose; D013004:Somatostatin; D014044:Tolbutamide