ASSESSMENT OF INSULIN-RESISTANCE IN ACROMEGALY ASSOCIATED WITH DIABETES-MELLITUS BEFORE AND AFTER TRANSSPHENOIDAL ADENOMECTOMY

With a euglycemic hyperinsulinemic clamp method, whole-body insulin re sistance was assessed in 6 cases with acromegaly associated with diabe tes mellitus before and after transsphenoidal adenomectomy. The glucos e infusion rate (GIR) correlated well with the plasma IGF-I level but poorly with that of GH. Further improvement in insulin sensitivity occ urred 3-4 months after operation without substantial changes in plasma levels of both GH and IGF-I or glycemic control. These results indica te that GH excess can induce insulin resistance in association with pl asma IGF-I and also through undefined secondary effect.