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Fast two-layer two-photon imaging of neuronal cell populations using an electrically tunable lens.

ABSTRACT: Functional two-photon Ca(2+)-imaging is a versatile tool to study the dynamics of neuronal populations in brain slices and living animals. However, population imaging is typically restricted to a single two-dimensional image plane. By introducing an electrically tunable lens into the excitation path of a two-photon microscope we were able to realize fast axial focus shifts within 15 ms. The maximum axial scan range was 0.7 mm employing a 40x NA0.8 water immersion objective, plenty for typically required ranges of 0.2-0.3 mm. By combining the axial scanning method with 2D acousto-optic frame scanning and random-access scanning, we measured neuronal population activity of about 40 neurons across two imaging planes separated by 40 μm and achieved scan rates up to 20-30 Hz. The method presented is easily applicable and allows upgrading of existing two-photon microscopes for fast 3D scanning.

SUBMITTER: Grewe BF

PROVIDER: S-EPMC3130587 | biostudies-other | 2011 Jul

REPOSITORIES: biostudies-other

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