Optimized [1-13C]glucose infusion protocol for 13C magnetic resonance spectroscopy at 3 T of human brain glucose metabolism under euglycemic and hypoglycemic conditions

The effect of insulin-induced hypoglycemia on cerebral glucose metabolism is largely unknown. C-13 MRS is a unique tool to study cerebral glucose metabolism, but the concurrent requirement for [1-C-13]glucose administration limits its use under hypoglycemic conditions. To facilitate C-13 MRS data analysis we designed separate [1-C-13]glucose infusion protocols for hyperinsulinemic euglycemic and hypoglycemic clamps in such a way that plasma isotopic enrichment of glucose was stable and comparable under both glycemic conditions. C-13 MR spectra were acquired with optimized C-13 MRS measurement techniques to obtain high quality C-13 MR spectra with these protocols. (C) 2009 Elsevier B.V. All rights reserved.