Avtor/Urednik     Perko, Denis; Zaletel, Marjan
Naslov     Pomen astrocitov, obžilnih živčnih vlaken in možganskega žilnega endotelija pri regulaciji možganskega krvnega pretoka
Prevedeni naslov     Role of astrocytes, perivascular nerves and cerebrovascular endothelium in the regulation of cerebral blood flow
Tip     članek
Vir     Med Razgl
Vol. in št.     Letnik 47, št. 3
Leto izdaje     2008
Obseg     str. 283-91
Jezik     slo
Abstrakt     For normal function brain requires proper supply of oxygen and glucose in a timely and local manner. This is achieved through intercellular communications, a process known as nerovascular coupling. At least that is what was believed till today. Recent studies showed us that this process besides activated perivascular neurons also involves astrocycites. Together they alter local vascular tone and so adjust perfusion to the spatial and temporal changes in brain activity. Cerebral blood vessels at the surface and within the brain are surrounded by nerve fibres that originate, respectively, from peripheral nerve ganglia and intrinsic brain neurons. Although of different origin and targeting distinct vascular beds, perivascular nerves similarly reglate cerebrovascular tone and therein brain perfusion. Astrocytes, cells with extensive contacts with both synapses and cerebral blood vessels, also participate in the increases in flow evoked by synaptic activity. Their structural organization indicates that they are uniquely positioned to shape the spatial distribution of the vascular responses that are evoked by neural activity. Astrocytic calcium is an important determinant of microvascular function and may regulate flow independently of synaptic activity. Ultimately, cerebrovascular endothelium exerts a profound influence on cerebral vessels and cerebral blood flow. The endothelium contributes to the resting tone of cerebral arteries and arterioles by tonically releasing nitric oxide. It may participate in neurovascular coupling by conducting local dilations to upstream arteries. So nowadays we speak about neuro-astrocyte-vascular tripartite unit.
Deskriptorji     CEREBROVASCULAR CIRCULATION
ENDOTHELIUM, VASCULAR
ASTROCYTES
CEREBRAL ARTERIES
NITRIC OXIDE
EPOPROSTENOL