A highly sensitive fluorescent indicator dye for calcium imaging of neural activity in vitro and in vivo. (9th January 2014)

• Record Type: Journal Article
• Authors: Tada, Mayumi; Takeuchi, Atsuya; Hashizume, Miki; Kitamura, Kazuo; Kano, Masanobu
• Is Part Of: European journal of neuroscience. Volume 39:Number 11(2014:Jun.)
• Page Start: 1720
• Page End: 1728
• Publication Date: 2014-01-09
• Subjects: Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.12476
• Languages: English
• ISSNs: 0953-816X

Abstract

<abstract abstract-type="main" id="ejn12476-abs-0001"> <title>Abstract</title> <p>Calcium imaging of individual neurons is widely used for monitoring their activity <italic>in vitro</italic> and <italic>in vivo</italic>. Synthetic fluorescent calcium indicator dyes are commonly used, but the resulting calcium signals sometimes suffer from a low signal‐to‐noise ratio (SNR). Therefore, it is difficult to detect signals caused by single action potentials (APs) particularly from neurons <italic>in vivo</italic>. Here we showed that a recently developed calcium indicator dye, Cal‐520, is sufficiently sensitive to reliably detect single APs both <italic>in vitro</italic> and <italic>in vivo</italic>. In neocortical neurons, calcium signals were linearly correlated with the number of APs, and the SNR was &gt; 6 for <italic>in vitro</italic> slice preparations and &gt; 1.6 for <italic>in vivo</italic> anesthetised mice. In cerebellar Purkinje cells, dendritic calcium transients evoked by climbing fiber inputs were clearly observed in anesthetised mice with a high SNR and fast decay time. These characteristics of Cal‐520 are a great advantage over those of Oregon Green BAPTA‐1, the most commonly used calcium indicator dye, for monitoring the activity of individual neurons both <italic>in vitro</italic> and <italic>in vivo</italic>.</p> </abstract>