Electrophysiological Examination of Glucose Transport into Motor Nerve Terminals in Mature Adult and Aged Rats
The rate of glucose uptake is different into nerve terminals innervating muscles composed of different fiber types (9). For example, glucose enters terminals innervating glycolytic muscles more rapidly than it enters those innervating oxidative muscles. Furthermore, there is a strong relationship between the efficiency of α-motoneuron energy metabolism, for which glucose is a major substrate, and the type of muscle fiber that the motor neuron innervates (12). Specifically, nerve terminals innervating oxidative muscles exhibit a greater capacity for oxidative enzyme activity than those innervating glycolytic muscles. Therefore, glucose transport into peripheral nerve terminals may be linked to its rate of utilization. Kinetic analyses of glucose uptake into synaptosomes and brain slices support this (3, 13).
KeywordsGlucose Uptake Glucose Transport Nerve Terminal Extensor Digitorum Longus Extensor Digitorum Longus Muscle
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