title: Real-time luminescence imaging of cellular ATP release.
abstract: Extracellular ATP and other purines are ubiquitous mediators of local intercellular signaling within the body. While the last two decades have witnessed enormous progress in uncovering and characterizing purinergic receptors and extracellular enzymes controlling purinergic signals, our understanding of the initiating step in this cascade, i.e., ATP release, is still obscure. Imaging of extracellular ATP by luciferin-luciferase bioluminescence offers the advantage of studying ATP release and distribution dynamics in real time. However, low-light signal generated by bioluminescence reactions remains the major obstacle to imaging such rapid processes, imposing substantial constraints on its spatial and temporal resolution. We have developed an improved microscopy system for real-time ATP imaging, which detects ATP-dependent luciferin-luciferase luminescence at ∼10 frames/s, sufficient to follow rapid ATP release with sensitivity of ∼10 nM and dynamic range up to 100 μM. In addition, simultaneous differential interference contrast cell images are acquired with infra-red optics. Our imaging method: (1) identifies ATP-releasing cells or sites, (2) determines absolute ATP concentration and its spreading manner at release sites, and (3) permits analysis of ATP release kinetics from single cells. We provide instrumental details of our approach and give several examples of ATP-release imaging at cellular and tissue levels, to illustrate its potential utility.
authors: Department of Physiology, Nagoya University, Graduate School of Medicine, Nagoya, Japan; FIRST Research Center for Innovative Nanobiodevices, Nagoya University, Nagoya, Japan. Electronic address: furuya@med.nagoya-u.ac.jp.
authors: Kishio
authors: K
authors: Furuya
authors: Department of Physiology, Nagoya University, Graduate School of Medicine, Nagoya, Japan. Electronic address: msokabe@med.nagoya-u.ac.jp.
authors: Masahiro
authors: M
authors: Sokabe
authors: Department of Physiology, Nagoya University, Graduate School of Medicine, Nagoya, Japan; Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM) - Hôtel-Dieu, and Department of Medicine, Université de Montréal, Montréal, Québec, Canada. Electronic address: ryszard.grygorczyk@umontreal.ca.
authors: Ryszard
authors: R
authors: Grygorczyk
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002138:Calibration; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D007700:Kinetics; D008321:Mammary Glands, Animal / Q000378:metabolism; D040542:Mechanotransduction, Cellular; D051379:Mice; D008813:Mice, Inbred ICR; D008856:Microscopy, Fluorescence / Q000379:methods; D008857:Microscopy, Interference; D061251:Primary Cell Culture; D051381:Rats; D013312:Stress, Physiological
chemical_list: D000255:Adenosine Triphosphate
keywords: ATP release; Hypotonic stress; Infra-red imaging; Luciferin–luciferase; Luminescence microscopy; Mechanical stimulation