Modeling secondary messenger pathways in neurovascular coupling.
Neurovascular coupling is the well-documented link between neural stimulation and constriction or dilation of the surrounding vasculature. Glial cells mediate this response via their unique anatomy, which connects neurons to arterioles. It is believed that calcium transients and the release of secondary messengers by these cells influence the vascular response. We present a model of intracellular calcium dynamics in an astrocyte (glial cell) and show that stable oscillatory behaviour is possible under certain conditions. We then couple this to a novel model for the relationship between calcium concentration and the production of vasoactive secondary messengers through a fatty-acid intermediate. The two secondary messengers modelled are epoxyeicosatrienoic and 20-hydroxyeicosatetraenoic acids (EET and 20-HETE, respectively). These secondary messengers are produced on different time scales, and we show how this supports the observation that the vasculature dilates rapidly in response to neural stimulation, before returning to baseline levels on a slower time scale.
Department of Mathematics and Statistics, University of Canterbury, Christchurch, New Zealand.
James
J
Hadfield
Michael J
MJ
Plank
Tim
T
David
D001253:Astrocytes / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism; D008959:Models, Neurological; D009131:Muscle, Smooth, Vascular / Q000098:blood supply / Q000294:innervation / Q000378:metabolism / Q000502:physiology*; D014661:Vasoconstriction; D014664:Vasodilation
D006893:Hydroxyeicosatetraenoic Acids; C055987:20-hydroxy-5,8,11,14-eicosatetraenoic acid