Welcome to Gaia! :: View User's Journal | Gaia Journals

Response to aerial exposure and hypoxia in the oxidative stress parameters differed in intertidal N. concinna, whereas the antioxidant enzyme activities in sub-littoral specimens responded in the same way to both forms of stress ( Table 4). This fits with our observation that intertidal limpets respond more rigorously to air exposure than sub-littoral limpets, which maintained shell water PO2 at low levels independently of submergence state. Whereas sub-littoral limpets responded equally to air exposure and hypoxia, by inducing bez235 metabolism, intertidal limpets differentiate between air exposure, during which they remain aerobic and hypoxia during which anaerobic metabolites accumulate ( Weihe and Abele, 2008; Weihe, unpublished data). The most obvious difference with respect to the antioxidants occurs in the gills. Intertidal limpets reduce (SOD) activities, whereas in sub-littoral limpets gill SOD activity increases under both forms of stress.
Table 4.
Changes of oxidative stress parameters in intertidal and sub-littoral Nacella concinna upon exposure to air and hypoxia (2 kPa). Arrows indicate increase (↑) or decrease (↓) of enzyme activity. In case of pHa and redox potential (EmV) “↓” indicates acidification/reduction. No change observed is motor output indicated as “↔” and an initial decrease with subsequent slight recovery of a parameter by “↓↑” and “↓↑” stands for early transient decrease followed by recovery.