Astrocyte-mediated control of cerebral microcirculation.

Department of Neurology, University of California-San Francisco, Department of Veterans Affairs Medical Center, San Francisco, CA 94121, USA.
Trends in Neurosciences (Impact Factor: 13.58). 08/2003; 26(7):340-4; author reply 344-5. DOI: 10.1016/S0166-2236(03)00141-3
Source: PubMed

ABSTRACT Characterization of astrocyte Ca2+ dynamics has been a topic of considerable emphasis for more than a decade. Only recently, however, has the physiological significance of astrocyte Ca2+ signaling started to become clear. Several studies have shown that astrocyte Ca2+ levels become elevated in response to neuronal input and that this, in turn, influences synaptic activity. A novel function of astrocyte Ca2+ signaling has been described by Zonta et al., whereby neuron-induced astrocyte Ca2+ elevations can lead to secretion of vasodilatory substances from perivascular astrocyte endfeet, resulting in improved local blood flow. This finding represents a breakthrough in our knowledge both of astrocyte function and of the mechanism of activity-dependent cerebral blood flow regulation.

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