Zell- und systemphysiologische Untersuchungen der Temperaturtoleranz bei Fischen

• Other Authors: Mark, Felix Christopher
• Language: German
• Published: Staats- und Universitätsbibliothek [Host] 2004
• Subjects: Antarctic; The Antarctic; Antarc*
• Online Access: http://nbn-resolving.de/urn:nbn:de:gbv:46-diss000011089; http://webdoc.sub.gwdg.de/ebook/diss/Bremen/2004/E-Diss1108_Mark.pdf

Antarctic fish, temperature tolerance, oxygen limited thermal tolerance, NMR. - In an integrative approach, this thesis addressed thermal tolerance in temperate and Antarctic fish examining its functions, limits and mechanistic links between the organismic, cellular and molecular level. The role of oxygen in limiting thermal tolerance of the Antarctic eelpout P. brachycephalum was investigated in in vivo NMR experiments. Temperature effects on respiration, blood flow, intracellular pH and tissue oxygenation were studied under normoxia and hyperoxia. Thermal tolerance was limited by the capacities of the circulatory system supplying oxygen to the tissues. At a lower level of organismic complexity, thermal sensitivity of cellular energy allocation was studied in Antarctic fish. Organismic thermal limitations were not reflected at the cellular level. Provided with sufficient oxygen, cellular energy budgets show greater thermal tolerance than the organism. These findings corroborate that capacity limitations of the organismic level constrict thermal tolerance and support the recent concept of a systemic to molecular hierarchy. At the molecular level, temperature sensitive expression of mitochondrial uncoupling proteins (UCP) was studied . @Bremen, Univ., Diss., 2004