Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2
Abstract Introduction Ongoing ocean warming and acidification increasingly affect marine ecosystems, in particular around the Antarctic Peninsula. Yet little is known about the capability of Antarctic notothenioid fish to cope with rising temperature in acidifying seawater. While the whole animal le...
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ftbiomed:oai:biomedcentral.com:1742-9994-9-28 2023-05-15T13:42:30+02:00 Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 Strobel, Anneli Bennecke, Swaantje Leo, Elettra Mintenbeck, Katja Pörtner, Hans O Mark, Felix C 2012-10-18 http://www.frontiersinzoology.com/content/9/1/28 en eng BioMed Central Ltd. http://www.frontiersinzoology.com/content/9/1/28 Copyright 2012 Strobel et al.; licensee BioMed Central Ltd. Notothenioid Oxygen consumption Routine metabolic rate Extracellular pH (pHe) Intracellular pH (pHi) Mitochondrial respiration Acclimation Acid–base Research 2012 ftbiomed 2013-01-13T02:57:36Z Abstract Introduction Ongoing ocean warming and acidification increasingly affect marine ecosystems, in particular around the Antarctic Peninsula. Yet little is known about the capability of Antarctic notothenioid fish to cope with rising temperature in acidifying seawater. While the whole animal level is expected to be more sensitive towards hypercapnia and temperature, the basis of thermal tolerance is set at the cellular level, with a putative key role for mitochondria. This study therefore investigates the physiological responses of the Antarctic Notothenia rossii after long-term acclimation to increased temperatures (7°C) and elevated P CO 2 (0.2 kPa CO 2 ) at different levels of physiological organisation. Results For an integrated picture, we analysed the acclimation capacities of N. rossii by measuring routine metabolic rate (RMR), mitochondrial capacities (state III respiration) as well as intra- and extracellular acid–base status during acute thermal challenges and after long-term acclimation to changing temperature and hypercapnia. RMR was partially compensated during warm- acclimation (decreased below the rate observed after acute warming), while elevated P CO 2 had no effect on cold or warm acclimated RMR . Mitochondrial state III respiration was unaffected by temperature acclimation but depressed in cold and warm hypercapnia-acclimated fish. In both cold- and warm-exposed N. rossii , hypercapnia acclimation resulted in a shift of extracellular pH (pH e ) towards more alkaline values. A similar overcompensation was visible in muscle intracellular pH (pH i ). pH i in liver displayed a slight acidosis after warm normo- or hypercapnia acclimation, nevertheless, long-term exposure to higher P CO 2 was compensated for by intracellular bicarbonate accumulation. Conclusion The partial warm compensation in whole animal metabolic rate indicates beginning limitations in tissue oxygen supply after warm-acclimation of N. rossii . Compensatory mechanisms of the reduced mitochondrial capacities under chronic hypercapnia may include a new metabolic equilibrium to meet the elevated energy demand for acid–base regulation. New set points of acid–base regulation under hypercapnia, visible at the systemic and intracellular level, indicate that N. rossii can at least in part acclimate to ocean warming and acidification. It remains open whether the reduced capacities of mitochondrial energy metabolism are adaptive or would impair population fitness over longer timescales under chronically elevated temperature and P CO 2 . Other/Unknown Material Antarc* Antarctic Antarctic Peninsula Notothenia rossii BioMed Central Antarctic Antarctic Peninsula The Antarctic |
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BioMed Central |
op_collection_id |
ftbiomed |
language |
English |
topic |
Notothenioid Oxygen consumption Routine metabolic rate Extracellular pH (pHe) Intracellular pH (pHi) Mitochondrial respiration Acclimation Acid–base |
spellingShingle |
Notothenioid Oxygen consumption Routine metabolic rate Extracellular pH (pHe) Intracellular pH (pHi) Mitochondrial respiration Acclimation Acid–base Strobel, Anneli Bennecke, Swaantje Leo, Elettra Mintenbeck, Katja Pörtner, Hans O Mark, Felix C Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 |
topic_facet |
Notothenioid Oxygen consumption Routine metabolic rate Extracellular pH (pHe) Intracellular pH (pHi) Mitochondrial respiration Acclimation Acid–base |
description |
Abstract Introduction Ongoing ocean warming and acidification increasingly affect marine ecosystems, in particular around the Antarctic Peninsula. Yet little is known about the capability of Antarctic notothenioid fish to cope with rising temperature in acidifying seawater. While the whole animal level is expected to be more sensitive towards hypercapnia and temperature, the basis of thermal tolerance is set at the cellular level, with a putative key role for mitochondria. This study therefore investigates the physiological responses of the Antarctic Notothenia rossii after long-term acclimation to increased temperatures (7°C) and elevated P CO 2 (0.2 kPa CO 2 ) at different levels of physiological organisation. Results For an integrated picture, we analysed the acclimation capacities of N. rossii by measuring routine metabolic rate (RMR), mitochondrial capacities (state III respiration) as well as intra- and extracellular acid–base status during acute thermal challenges and after long-term acclimation to changing temperature and hypercapnia. RMR was partially compensated during warm- acclimation (decreased below the rate observed after acute warming), while elevated P CO 2 had no effect on cold or warm acclimated RMR . Mitochondrial state III respiration was unaffected by temperature acclimation but depressed in cold and warm hypercapnia-acclimated fish. In both cold- and warm-exposed N. rossii , hypercapnia acclimation resulted in a shift of extracellular pH (pH e ) towards more alkaline values. A similar overcompensation was visible in muscle intracellular pH (pH i ). pH i in liver displayed a slight acidosis after warm normo- or hypercapnia acclimation, nevertheless, long-term exposure to higher P CO 2 was compensated for by intracellular bicarbonate accumulation. Conclusion The partial warm compensation in whole animal metabolic rate indicates beginning limitations in tissue oxygen supply after warm-acclimation of N. rossii . Compensatory mechanisms of the reduced mitochondrial capacities under chronic hypercapnia may include a new metabolic equilibrium to meet the elevated energy demand for acid–base regulation. New set points of acid–base regulation under hypercapnia, visible at the systemic and intracellular level, indicate that N. rossii can at least in part acclimate to ocean warming and acidification. It remains open whether the reduced capacities of mitochondrial energy metabolism are adaptive or would impair population fitness over longer timescales under chronically elevated temperature and P CO 2 . |
format |
Other/Unknown Material |
author |
Strobel, Anneli Bennecke, Swaantje Leo, Elettra Mintenbeck, Katja Pörtner, Hans O Mark, Felix C |
author_facet |
Strobel, Anneli Bennecke, Swaantje Leo, Elettra Mintenbeck, Katja Pörtner, Hans O Mark, Felix C |
author_sort |
Strobel, Anneli |
title |
Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 |
title_short |
Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 |
title_full |
Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 |
title_fullStr |
Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 |
title_full_unstemmed |
Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2 |
title_sort |
metabolic shifts in the antarctic fish notothenia rossii in response to rising temperature and pco2 |
publisher |
BioMed Central Ltd. |
publishDate |
2012 |
url |
http://www.frontiersinzoology.com/content/9/1/28 |
geographic |
Antarctic Antarctic Peninsula The Antarctic |
geographic_facet |
Antarctic Antarctic Peninsula The Antarctic |
genre |
Antarc* Antarctic Antarctic Peninsula Notothenia rossii |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Notothenia rossii |
op_relation |
http://www.frontiersinzoology.com/content/9/1/28 |
op_rights |
Copyright 2012 Strobel et al.; licensee BioMed Central Ltd. |
_version_ |
1766168602186088448 |