In Vivo Two-photon Calcium Imaging in Dendrites of Rabies Virus-labeled V1 Corticothalamic Neurons.

ABSTRACT: Monitoring neuronal activity in vivo is critical to understanding the physiological or pathological functions of the brain. Two-photon Ca²⁺ imaging in vivo using a cranial window and specific neuronal labeling enables real-time, in situ, and long-term imaging of the living brain. Here, we constructed a recombinant rabies virus containing the Ca²⁺ indicator GCaMP6s along with the fluorescent protein DsRed2 as a baseline reference to ensure GCaMP6s signal reliability. This functional tracer was applied to retrogradely label specific V1-thalamus circuits and detect spontaneous Ca²⁺ activity in the dendrites of V1 corticothalamic neurons by in vivo two-photon Ca²⁺ imaging. Notably, we were able to record single-spine spontaneous Ca²⁺ activity in specific circuits. Distinct spontaneous Ca²⁺ dynamics in dendrites of V1 corticothalamic neurons were found for different V1-thalamus circuits. Our method can be applied to monitor Ca²⁺ dynamics in specific input circuits in vivo, and contribute to functional studies of defined neural circuits and the dissection of functional circuit connections.

SUBMITTER: Tang Y 

PROVIDER: S-EPMC7186288 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature