Basal- and insulin-stimulated substrate metabolism in patients with active acromegaly before and after adenomectomy.

Active acromegaly is characterized by inappropriate tissue growth, increased mortality, and perturbations of intermediary metabolism. It is, in general, not well described to which extent these disturbances are normalized after treatment of the disease. To further assess basal and insulin stimulated fuel metabolism in acromegaly six patients with monotropic GH excess were each studied approximately 1 month prior to and 2 months after successful selective pituitary adenomectomy and compared to a control population of seven subjects. The studies consisted of a 3-h basal postabsorptive period and a 2-h hyperinsulinaemic (0.4 mU/kg/min) euglycemic clamp and the methods employed included isotopical measurement of glucose turnover, indirect calorimetry, and the forearm technique. When compared to the control subjects the patients with acromegaly were preoperatively and in the basal state characterized by: 1) increased circulating concentrations of GH, insulin, and C-peptide (P less than 0.05); 2) increased plas...