Abstract
We applied two-photon laser-scanning microscopy (TPLSM) to motion-sensitive visual interneurons of the fly to study Ca 2+ dynamics in vivo at a higher spatial and temporal resolution than possible with conventional fluorescence microscopy. Based on a custom-built two-photon microscope, we performed line scans to measure changes in presynaptic Ca 2+ concentrations elicited by visual stimulation. We used a fast avalanche photodiode (APD) with a high quantum efficiency to detect even low levels of emitted fluorescence. Our experiments show that our in vivo preparation is amenable to TPLSM: with excitation intensities low enough not to cause photodamage, activity-dependent fluorescence changes of Ca 2+-sensitive dyes can be detected in small neuronal branches. The performance of two-photon and conventional Ca 2+ imaging carried out consecutively at the same neuron is compared and it is demonstrated that two-photon imaging allows us to detect differences in Ca 2+ dynamics between individual neurites.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Biochemical and Biophysical Research Communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
