title: Reactive oxygen species production and discontinuous gas exchange in insects.
abstract: While biochemical mechanisms are typically used by animals to reduce oxidative damage, insects are suspected to employ a higher organizational level, discontinuous gas exchange mechanism to do so. Using a combination of real-time, flow-through respirometry and live-cell fluorescence microscopy, we show that spiracular control associated with the discontinuous gas exchange cycle (DGC) in Samia cynthia pupae is related to reactive oxygen species (ROS). Hyperoxia fails to increase mean ROS production, although minima are elevated above normoxic levels. Furthermore, a negative relationship between mean   and mean ROS production indicates that higher ROS production is generally associated with lower  . Our results, therefore, suggest a possible signalling role for ROS in DGC, rather than supporting the idea that DGC acts to reduce oxidative damage by regulating ROS production.
authors.affiliation: Department of Conservation Ecology and Entomology, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Leigh
authors.initials: L
authors.lastname: Boardman
authors.forename: John S
authors.initials: JS
authors.lastname: Terblanche
authors.forename: Stefan K
authors.initials: SK
authors.lastname: Hetz
authors.forename: Elrike
authors.initials: E
authors.lastname: Marais
authors.forename: Steven L
authors.initials: SL
authors.lastname: Chown
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009036:Moths / Q000378:metabolism*; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D011679:Pupa / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D017382:Reactive Oxygen Species; D002245:Carbon Dioxide; D010100:Oxygen