Metabolic plasticity and critical temperatures for aerobic scope in a eurythermal marine invertebrate (Littorina saxatilis, Gastropoda: Littorinidae) from different latitudes

摘要: SUMMARY Effects of latitudinal cold adaptation and acclimation on metabolic rates aerobic scope were studied in the eurythermal marine gastropod Littorina saxatilis from temperate North Sea sub-arctic White areas. Animals acclimated for 6-8 weeks at control temperature (13°C) or 4°C, their respiration rates measured during acute temperature change (1-1.5°C h-1) a range between 0°C 32°C. In parallel, accumulation anaerobic end products changes in energy status monitored. Starting 0°C, L. rose quickly with increasing temperatures up to a point or slightly above respective temperature. Beyond this value, thermal sensitivity oxygen consumption rate (VO2) greatly decreased wide, 15°C experimental temperatures. This regulation was also reflected activation metabolism (Ea), which approximately seven times lower at Arrhenius breakpoint (ABTs) than temperatures below ABTs. Warming progressively led discrepancy energy demand production, as demonstrated by decrease levels high-energy phosphates [phosho-L-arginine (PLA) ATP], resulted onset anaerobiosis critically high temperatures, indicating limitation scope. The comparison anaerobic air water suggests that heat-induced is due insufficient supply tissues Cold an increase aerobic considerable downward shift upper critical but not L. saxatilis. Limited plasticity response acclimation snails compared North counterparts that depression occurs overwintering under more extreme winter conditions Sea.