Electrical stimulation is the clinical standard for cardiac pacing. Although highly effective in controlling cardiac rhythm, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its applications. Optogenetic pacing of the heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids the shortcomings in electrical stimulation. Drosophila melanogaster, which is a powerful model organism with orthologs of nearly 75% of human disease genes, has not been studied for optogenetic pacing in the heart. Here, we developed a non-invasive integrated optical pacing and optical coherence microscopy (OCM) imaging system to control the heart rhythm of Drosophila at different developmental stages using light. The OCM system is capable of providing high imaging speed (130 frames/s) and ultrahigh imaging resolutions (1.5 μm and 3.9 μm for axial and transverse resolutions, respectively). A light-sensitive pacemaker was developed in Drosophila by specifically expressing the light-gated cation channel, channelrhodopsin-2 (ChR2) in transgenic Drosophila heart. We achieved non-invasive and specific optical control of the Drosophila heart rhythm throughout the fly’s life cycle (larva, pupa, and adult) by stimulating the heart with 475 nm pulsed laser light. Heart response to stimulation pulses was monitored non-invasively with OCM. This integrated non-invasive optogenetic control and in vivo imaging technique provides a novel platform for performing research studies in developmental cardiology.
Aneesh Alex, Airong Li, Jing Men, Jason Jerwick, Rudolph E. Tanzi, Chao Zhou, Zhan Zhang, and Xianxu Zeng, "An integrated optical coherence microscopy imaging and optical stimulation system for optogenetic pacing in Drosophila melanogaster
(Conference Presentation)," Proc. SPIE 9697, Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XX, 96971A (Presented at SPIE BiOS: February 16, 2016; Published: 26 April 2016); https://doi.org/10.1117/12.2214671.4848635698001.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the conference proceedings. They include the speaker's narration along with a video recording of the presentation slides and animations. Many conference presentations also include full-text papers. Search and browse our growing collection of more than 12,000 conference presentations, including many plenary and keynote presentations.
Monte Carlo based light propagation models to improve efficacy of biophotonics based therapeutics of hollow organs and solid tumours including photodynamic therapy and photobiomodulation (Conference Presentation)