Arteriole dilation to synaptic activation that is sub-threshold to astrocyte endfoot Ca2+ transients.
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ABSTRACT:
SUBMITTER: Institoris A
PROVIDER: S-EPMC4640329 | biostudies-other | 2015 Sep
REPOSITORIES: biostudies-other
Publications
Arteriole dilation to synaptic activation that is sub-threshold to astrocyte endfoot Ca2+ transients.
Institoris Ádám Á Rosenegger David George DG Gordon Grant Robert GR
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20150701 9
Ca(2+)-dependent pathways in neurons and astrocyte endfeet initiate changes in arteriole diameter to regulate local brain blood flow. Whether there exists a threshold of synaptic activity in which arteriole diameter is controlled independent of astrocyte endfeet Ca(2+) remains unclear. We used two-photon fluorescence microscopy to examine synaptically evoked synthetic or genetic Ca(2+) indicator signals around penetrating arterioles in acute slices of the rat neocortex. We discovered a threshold ...[more]
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