title: Neuronal activity-dependent regulation of retinal blood flow.
abstract: Blood flow in the retina is intrinsically regulated to meet the metabolic demands of its constituent cells. Flickering light or stationary contrast reversals induce an increase in blood flow within seconds of the stimulus onset. This phenomenon is thought to compensate for an increase in ganglion cell activity and energy consumption. Ganglion cell activity is in turn dependent on signals from photoreceptors, bipolar cells, horizontal cells and amacrine cells. The physiological properties of these neurons determine how each type is affected by a particular light characteristic. Neuronal activity then triggers the release of signalling molecules that dilate local blood vessels and increase blood flow. Nitric oxide has been implicated as an important mediator, but metabolites of arachidonic acid may also be involved. Detailed elucidation of these mechanisms, together with advances in imaging technology, may facilitate the use of neurovascular tests to improve the detection of retinal damage in pathological conditions.
authors.affiliation: Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Noonan
authors.affiliation: Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia.|Singapore Eye Research Institute, Department of Ophthalmology, National University of Singapore, Singapore.|Duke-NUS Graduate Medical School, National University of Singapore, Singapore.
authors.forename: Ecosse L
authors.initials: EL
authors.lastname: Lamoureux
authors.affiliation: Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Marc
authors.initials: M
authors.lastname: Sarossy
mesh_terms: D000818:Animals; D015350:Contrast Sensitivity / Q000502:physiology; D004596:Electroretinography; D005074:Evoked Potentials, Visual / Q000502:physiology; D006801:Humans; D008027:Light; D012039:Regional Blood Flow / Q000502:physiology*; D055351:Retinal Neurons / Q000502:physiology*; D012171:Retinal Vessels / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology
keywords: arachidonic acid; ganglion cell; neurovascular coupling; nitric oxide; retina