Insulin enhances glucose-stimulated insulin secretion in healthy humans

• DOI: 10.1073/pnas.1000002107
• Publication Date: 2010-02-23T03:35:31Z
• Authors: Clara Bouche; Ximena Lopez; Amy Fleischman; Aaron M. Cypess; Sheila O'Shea; Darko Stefanovski; Richard N. Bergman; Eduard Rogatsky; Daniel T. Stein; C. Ronald Kahn; Rohit N. Kulkarni; Allison B. Goldfine
• Keywords: Hyperinsulinemia; Insulin oscillation; C-peptide

Islet β-cells express both insulin receptors and insulin-signaling proteins. Recent evidence from rodents in vivo islets isolated or humans suggests that the signaling pathway is physiologically important for glucose sensing. We evaluated whether regulates β-cell function healthy vivo. Glucose-induced secretion was assessed following 4-h saline (low insulin/sham clamp) isoglycemic-hyperinsulinemic (high insulin) clamps using B28-Asp could be immunologically distinguished endogenous insulin. Insulin C-peptide clearance were to understand impact of hyperinsulinemia on estimates function. Preexposure exogenous increased secretory response by ≈40%. also increased, although not level predicted saturated at hyperinsulinemia, but metabolic C-peptide, infusion stable isotope–labeled modestly during hyperinsulinemic clamp. These studies demonstrate potentiates glucose-stimulated humans. In addition, increases clearance, which may lead modest underestimation when these methods prolonged dynamic testing.