Metabolic Communication between Astrocytes and Neurons via Bicarbonate-Responsive Soluble Adenylyl Cyclase Academic Article uri icon

Overview

MeSH Major

  • Adenylyl Cyclases
  • Astrocytes
  • Bicarbonates
  • Hippocampus
  • Neurons

abstract

  • Astrocytes are proposed to participate in brain energy metabolism by supplying substrates to neurons from their glycogen stores and from glycolysis. However, the molecules involved in metabolic sensing and the molecular pathways responsible for metabolic coupling between different cell types in the brain are not fully understood. Here we show that a recently cloned bicarbonate (HCO₃⁻) sensor, soluble adenylyl cyclase (sAC), is highly expressed in astrocytes and becomes activated in response to HCO₃⁻ entry via the electrogenic NaHCO₃ cotransporter (NBC). Activated sAC increases intracellular cAMP levels, causing glycogen breakdown, enhanced glycolysis, and the release of lactate into the extracellular space, which is subsequently taken up by neurons for use as an energy substrate. This process is recruited over a broad physiological range of [K⁺](ext) and also during aglycemic episodes, helping to maintain synaptic function. These data reveal a molecular pathway in astrocytes that is responsible for brain metabolic coupling to neurons.

publication date

  • September 20, 2012

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC3630998

Digital Object Identifier (DOI)

  • 10.1016/j.neuron.2012.08.032

PubMed ID

  • 22998876

Additional Document Info

start page

  • 1094

end page

  • 104

volume

  • 75

number

  • 6