Calcium ions generate versatile intracellular signals that control key functions in all types of neurons. Imaging calcium in neurons is of particularly importance because calcium signals exert their highly speciﬁc functions in well-deﬁned cellular sub-compartments. Each action potential triggers a large increase in neuronal intracellular calcium concentration, which then quickly (within milliseconds) returns to the pre-activation baseline. Their frequency may specify neuronal morphology and acquisition of neurotransmitter phenotype.
Fig. 1 Neuronal Calcium Signaling
Single neuronal calcium dynamics can be measured by confocal microscopy. Activity of multiple individual neurons (and of their dendritic or axonal compartments) can be measured using in vivo two-photon microscopy.
Here in Acroscell, we provide both in vitro
Culture neuronal cells
Cell lines with neuronal calcium channel expression
and in vivo
Anesthesia or awake animal’s calcium signaling test
To test neuronal in vivo calcium signals, we use mice expressing calcium-sensitive fluorescent proteins (such as GCaMP6f) on Thy1 promoter. GCaMP6f can also be expressed in wild-type mice or transgenic mouse models of disease.
Fig.2 Calcium imaging in the motor cortex of head-ﬁxed mice engaged in an olfactory-related choice behavior with lick/no lick response.
Easier than patch-clamp, high-throughput screening.
Multiple calcium indicators (Fluo-4, Fluo-8, Rhod-2 for calcium concentration detection; fura-2 for measuring actual cellular calcium concentrations) selections for evaluating dose-dependent curve.
Mice expressing calcium-sensitive fluorescent proteins (such as GCaMP6) on Thy1 promoter. GCaMP6 can also be expressed in wild-type mice or transgenic mouse models of disease.
Not only for study of membrane calcium channels, but also intracellular Ca2+ store dynamics.
Komiyama, T., et al. Learning-related ﬁne-scale speciﬁcity imaged in motor cortex circuits of behaving mice. Nature. 2010, 464: 1182–1186.
Grienberger C, Konnerth A. Imaging Calcium in Neurons. Neuron. 2012; 73: 862–885.