PT  - JOURNAL ARTICLE
AU  - Richard Piet
AU  - Craig E. Jahr
TI  - Glutamatergic and Purinergic Receptor-Mediated Calcium Transients in Bergmann Glial Cells
AID  - 10.1523/JNEUROSCI.0462-07.2007
DP  - 2007 Apr 11
TA  - The Journal of Neuroscience
PG  - 4027--4035
VI  - 27
IP  - 15
4099  - http://www.jneurosci.org/content/27/15/4027.short
4100  - http://www.jneurosci.org/content/27/15/4027.full
SO  - J. Neurosci.2007 Apr 11; 27
AB  - Astrocytes respond to neuronal activity with [Ca2+]i increases after activation of specific receptors. Bergmann glial cells (BGs), astrocytes of the cerebellar molecular layer (ML), express various receptors that can mobilize internal Ca2+. BGs also express Ca2+ permeable AMPA receptors that may be important for maintaining the extensive coverage of Purkinje cell (PC) excitatory synapses by BG processes. Here, we examined Ca2+ signals in single BGs evoked by synaptic activity in cerebellar slices. Short bursts of high-frequency stimulation of the ML elicited Ca2+ transients composed of a small-amplitude fast rising phase, followed by a larger and slower rising phase. The first phase resulted from Ca2+ influx through AMPA receptors, whereas the second phase required release of Ca2+ from internal stores initiated by P2 purinergic receptor activation. We found that such Ca2+ responses could be evoked by direct activation of neurons releasing ATP onto BGs or after activation of metabotropic glutamate receptor 1 on these neurons. Moreover, examination of BG and PC responses to various synaptic stimulation protocols suggested that ML interneurons are likely the cellular source of ATP.