The physiological response of the marine platyhelminthMacrostomum lignanoto different environmental oxygen concentrations

• DOI: 10.1242/jeb.081984
• Publication Date: 2013-03-27T01:35:47Z
• Authors: Georgina A. River...; Ulf Bickmeyer; Doris Abele
• Keywords: Mitochondrial ROS; Cellular respiration

Summary Respiration rate of meiofauna is difficult to measure, and the response variations in environmental oxygen concentrations has so far been mainly addressed through behavioral investigation. We investigated effect different on physiology marine platyhelminth Macrostomum lignano. was measured using batches 20 animals a glass microtiter plate equipped with optical sensor spots. At higher saturations (>12kPa), showed clear oxyconforming behavior. However, below this values, flatworms kept respiration rates constant at 0.064±0.001 nmol O2 l-1 h-1 ind-1 down 3 kPa PO2, increased 30% that were reoxygenated after enduring period 1.5h anoxia. Physiological changes related tissue oxygenation assessed live imaging techniques fluorophores maintained normoxic (21 kPa), hyperoxic (40 near anoxic (≈0 kPa) conditions subjected anoxia-reoxygenation. Ageladine-A BCECF both indicated pHi under anoxia increases by about 0.07 0.10 units. Mitochondrial membrane potential, Δψm, compared (JC1). Staining ROS sensitive dyes, DHE for detection superoxide anion (O2•-) formation C-H2DFFDA other species aside from O2•- (H2O2, HOO• ONOO-), following reoxygenation treatment. Animals exposed hyperoxic, treatments displayed no significant differences formation, whereas mitochondrial as detected exposure lowest control group. M. lignano seems be tolerant wide range (being able maintain aerobic metabolism extremely low PO2 up conditions) which an essential prerequisite successfully dealing drastic occur within intertidal sediments.