First Author | Srinivasan R | Year | 2015 |
Journal | Nat Neurosci | Volume | 18 |
Issue | 5 | Pages | 708-17 |
PubMed ID | 25894291 | Mgi Jnum | J:222858 |
Mgi Id | MGI:5645832 | Doi | 10.1038/nn.4001 |
Citation | Srinivasan R, et al. (2015) Ca(2+) signaling in astrocytes from Ip3r2(-/-) mice in brain slices and during startle responses in vivo. Nat Neurosci 18(5):708-17 |
abstractText | Intracellular Ca(2+) signaling is considered to be important for multiple astrocyte functions in neural circuits. However, mice devoid of inositol triphosphate type 2 receptors (IP3R2) reportedly lack all astrocyte Ca(2+) signaling, but display no neuronal or neurovascular deficits, implying that astrocyte Ca(2+) fluctuations are not involved in these functions. An assumption has been that the loss of somatic Ca(2+) fluctuations also reflects a similar loss in astrocyte processes. We tested this assumption and found diverse types of Ca(2+) fluctuations in astrocytes, with most occurring in processes rather than in somata. These fluctuations were preserved in Ip3r2(-/-) (also known as Itpr2(-/-)) mice in brain slices and in vivo, occurred in end feet, and were increased by G protein-coupled receptor activation and by startle-induced neuromodulatory responses. Our data reveal previously unknown Ca(2+) fluctuations in astrocytes and highlight limitations of studies that used Ip3r2(-/-) mice to evaluate astrocyte contributions to neural circuit function and mouse behavior. |