Measurement of Local Glucose Utilization and Its Use in Localization of Functional Activity in the Central Nervous System of Animals and Man

Abstract

The brain is a complex, heterogeneous organ composed of many anatomical and functional components with markedly different levels of functional activity that vary independently with time and function. Other tissues are generally homogeneous with most of their cells functioning similarly and synchronously in response to a common stimulus or regulatory influence. The central nervous system, however, consists of innumerable subunits, each integrated into its own set of functional pathways and networks, and subserving only one or a few of the many activities in which the nervous system participates. This chapter discusses the measurement of local glucose utilization and its use in localization of functional activity in the central nervous system of man and animals. 2-deoxyglucose is transported bi-directionally between blood and brain by the same carrier that transports glucose across the blood–brain barrier. In the cerebral tissues it is phosphorylated by hexokinase to 2-deoxyglucose 6-phosphate. Deoxyglucose and glucose are, therefore, competitive substrates for both blood–brain transport and hexokinase-catalyzed phosphorylation.