Astrocyte-mediated control of cerebral microcirculation.
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.
Anderson
Christopher M
CM
Department of Neurology, University of California-San Francisco, Department of Veterans Affairs Medical Center, San Francisco, CA 94121, USA.
Nedergaard
Maiken
M
D000818:Animals; D001253:Astrocytes / Q000378:metabolism* / Q000502:physiology; D001921:Brain / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D002118:Calcium / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000502:physiology; D008833:Microcirculation / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D015398:Signal Transduction; D009435:Synaptic Transmission
D002118:Calcium