G Protein-Coupled Receptor-Mediated Calcium Signaling in Astrocytes

Abstract

Astrocytes express a large variety of G protein-coupled receptors (GPCRs) which mediate the transduction of extracellular signals into intracellular calcium responses. This transduction is provided by a complex network of biochemical reactions which mobilizes a wealth of possible calcium-mobilizing second messenger molecules. Inositol 1,4,5-trisphosphate is probably the best known of these molecules whose enzymes for its production and degradation are nonetheless calcium-dependent. We present a biophysical modeling approach based on the assumption of Michaelis-Menten enzyme kinetics, to effectively describe GPCRmediated astrocytic calcium signals. Our model is then used to study different mechanisms at play in stimulus encoding by shape and frequency of calcium oscillations in astrocytes. † Deceased June 5, 2015.

A Neuron-Glial Model of Exosomal Release in the Onset and Progression of Alzheimer's Disease

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