Meeting Abstract

23.1  Friday, Jan. 4  Endurance exercise does not alter oxidative capacity or activities of enzymatic antioxidants in killifish (Fundulus heteroclitus) GRIM, J.M.*; ASKINS, M.E.; CROCKETT, E.L.; Ohio University, Mt. Desert Island Biological Laboratory; John Bapst Memorial High School; Ohio University, Mt. Desert Island Biological Laboratory grimj@ohio.edu

Animals are protected from oxidative injury because reactive oxygen species (ROS) production is matched by antioxidants involved in detoxifying ROS. While exercise training in mammals increases oxidative capacities potentially elevating the risk of oxidative damage, it also results typically in enhanced activities of enzymatic antioxidants presumably leaving trained individuals sufficiently protected. It is unclear whether oxidative and antioxidant capacities in other vertebrates also respond to exercise. This study uses a modified Beamish-style swim tunnel to subject killifish to a 9-day exercise regime (intensity – 2.25 BL/sec for 6 hrs/day) in order to evaluate changes in oxidative capacities and enzymatic antioxidants. Oxidative capacities, as indicated by cytochrome c oxidase (CCO) and citrate synthase (CS), and the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were assayed from axial glycolytic muscle and heart ventricles at 15°C. Neither oxidative capacities nor activities of SOD or CAT differ significantly between treatment groups of killifish, indicating that activity level, over a nine day period, is not a determinant of oxidative or antioxidant capacities. Differences in activity level associated with temperature acclimation of poikilotherms should not confound our attempts to quantify the role of temperature in setting oxidative and antioxidant capacities in killifish. Supported by MDIBL�s NIEHS Center for Membrane Toxicity Studies (P30 ES003828-20) and Stan and Judy Fund (JMG), OU Research Challenge (ELC).