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Glial-neuronal interactions and brain energy metabolism

  • Angus M. Brown
  • Selva Baltan Tekkök
  • Bruce R. Ransom

Abstract

Golgi, more than a century ago, suggested that glial cells provide nutritive support for neurons. He based this on his microscopic observations that glial cells are positioned between blood vessels and neurons, and their endfeet intimately surround blood vessels (Andriezen, 1893; Cajal, 1995). The anatomic arrangement of astrocytes, neurons and capillaries suggested that nutrients might be taken up preferentially by astrocytes. Astrocytes would then ‘share’ these nutrients with nearby neurons (Figure 11.1A). This old idea gained a degree of modern plausibility as more was learned about brain energy metabolism, and it was discovered that astrocytes are the only cells in the mammalian brain that contain significant glycogen (Cataldo and Broadwell, 1986a), the storage form of glucose. These refinements in the evolution of the nutritive hypothesis are shown in Figure 11.1B. The transfer of energy substrate (e.g. glucose or monocarboxylates) occurs across brain extracellular space (ECS), which is so narrow that molecules released from one cell diffuse almost instantly to adjacent cells (Nicholson, 1995). A crucial permissive feature of this scheme is that nearly every neuron in the brain shares common ECS with adjacent astrocytes.

Keywords

Vasoactive Intestinal Peptide Glycogen Content Neuronal Signaling Compound Action Potential Cereb Blood Flow 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Abbreviations

ANLSH

Astrocyte-neuron lactate shuttle hypothesis

ATP

Adenosine triphosphate

CAP

Compound action potential

CIN

Cinnamic acid

CNS

Central nervous system

ECS

Extracellular space

FDG PET

18F-deoxyglucose positron emission tomography

[glucose]o

Extracellular glucose concentration

G

6-P: Glucose-6-phosphate

GFAP

Glial fibrillary acidic protein

Gln

Glutamine

Glu

Glutamate

Glut

1,3,4 Glucose transporter 1,3,4

GS

Glutamine synthetase

[K+]o

Extracellular potassium ion concentration

Lac

Lactate

LDH

Lactate dehydrogenase

MCT

Monocarboxylate transporters

MON

Mouse optic nerve

NADPH

Nicotinamide adenine dinucleotide phosphate hydrogenase

Pyr

Pyruvate

VIP

Vasoactive intestinal peptide

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Copyright information

© Springer Science+Business Media New York 2004

Authors and Affiliations

  • Angus M. Brown
    • 1
  • Selva Baltan Tekkök
    • 2
  • Bruce R. Ransom
    • 2
  1. 1.MRC Applied Neuroscience Group, Biomedical SciencesUniversity of NottinghamNottinghamUK
  2. 2.Department of NeurologyUniversity of WashingtonSeattleUSA

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