title: Regulation of cerebral blood flow.
abstract: The control of cerebral blood flow is complex, and only beginning to be elucidated. Studies have identified three key regulatory paradigms. The first is cerebral pressure autoregulation, which maintains a constant flow in the face of changing cerebral perfusion pressure. Flow-metabolism coupling refers to the brains ability to vary blood flow to match metabolic activity. An extensive arborization of perivascular nerves also serves to modulate cerebral blood flow, so-called neurogenic regulation. Central to these three paradigms are two cell types: endothelium and astrocytes. The endothelium produces several vasoactive factors that are germane to the regulation of cerebral blood flow: nitric oxide, endothelium-dependent hyperpolarization factor, the eicosanoids, and the endothelins. Astrocytic foot processes directly abut the blood vessels, and play a key role in regulation of cerebral blood flow. Lastly, new research has been investigating cell-cell communication at the microvascular level. Several lines of evidence point to the ability of the larger proximal vessels to coordinate vasomotor responses downstream.
authors.affiliation: Department of Neurological Surgery, University of Washington, Seattle, WA 98195, USA.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Peterson
authors.forename: Zhengfeng
authors.initials: Z
authors.lastname: Wang
authors.forename: Gavin
authors.initials: G
authors.lastname: Britz