Nakajima, Ryuichi Baker, Bradley J. 2024-01-19T21:03:54Z 2024-01-19T21:03:54Z 2021-09-05 2018-12-19 0022-3727 https://pubs.kist.re.kr/handle/201004/120563 To understand the circuitry of the brain, it is essential to clarify the functional connectivity among distinct neuronal populations. For this purpose, neuronal activity imaging using genetically-encoded calcium sensors such as GCaMP has been a powerful approach due to its cell-type specificity. However, calcium (Ca2+) is an indirect measure of neuronal activity. A more direct approach would be to use genetically encoded voltage indicators (GEVIs) to observe subthreshold, synaptic activities. The GEVI, ArcLight, which exhibits large fluorescence transients in response to voltage, was expressed in excitatory neurons of the mouse CA1 hippocampus. Fluorescent signals in response to the electrical stimulation of the Schaffer collateral axons were observed in brain slice preparations. ArcLight was able to map both excitatory and inhibitory inputs projected to excitatory neurons. In contrast, the Ca2+ signal detected by GCaMP6f, was only associated with excitatory inputs. ArcLight and similar voltage sensing probes are also becoming powerful paradigms for functional connectivity mapping of brain circuitry. English IOP PUBLISHING LTD HYBRID VOLTAGE SENSOR FLUORESCENT PROTEIN IN-VIVO SYNAPTIC POTENTIALS ELECTRICAL-ACTIVITY PYRAMIDAL NEURONS BRAIN CONNECTIVITY INTERNEURONS DYNAMICS Mapping of excitatory and inhibitory postsynaptic potentials of neuronal populations in hippocampal slices using the GEVI, ArcLight Article 10.1088/1361-6463/aae2e3 1 JOURNAL OF PHYSICS D-APPLIED PHYSICS, v.51, no.50 JOURNAL OF PHYSICS D-APPLIED PHYSICS 51 50 scie scopus 000448153600001 2-s2.0-85055566901 Physics, Applied Physics Article HYBRID VOLTAGE SENSOR FLUORESCENT PROTEIN IN-VIVO SYNAPTIC POTENTIALS ELECTRICAL-ACTIVITY PYRAMIDAL NEURONS BRAIN CONNECTIVITY INTERNEURONS DYNAMICS ArcLight GCaMP GEVI GECI hippocampus synaptic excitation synaptic inhibition