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Göteborgs universitets publikationer

Cardiorespiratory upregulation during seawater acclimation in rainbow trout: effects on gastrointestinal perfusion and postprandial responses

Författare och institution:
Jeroen Brijs (Institutionen för biologi och miljövetenskap); Albin Gräns (-); Andreas Ekström (Institutionen för biologi och miljövetenskap); Catharina Olsson (Institutionen för biologi och miljövetenskap); Michael Axelsson (Institutionen för biologi och miljövetenskap); Erik Sandblom (Institutionen för biologi och miljövetenskap)
Publicerad i:
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 310 ( 9 ) s. R858-R865
ISSN:
0363-6119
Publikationstyp:
Artikel, refereegranskad vetenskaplig
Publiceringsår:
2016
Språk:
engelska
Fulltextlänk:
Sammanfattning (abstract):
Increased gastrointestinal blood flow is essential for euryhaline fishes to maintain osmotic homeostasis during the initial phase of a transition from freshwater to seawater. However, the cardiorespiratory responses and hemodynamic changes required for a successful long-term transition to seawater remain largely unknown. In the present study, we simultaneously measured oxygen consumption rate ((M)over dot(O2)), cardiac output (CO), heart rate (HR), and gastrointestinal blood flow (GBF) in rainbow trout (Oncorhynchus mykiss) acclimated to either freshwater or seawater for at least 6 wk. Seawater-acclimated trout displayed significantly elevated ((M)over dot(O2)) (day: 18%, night: 19%), CO (day: 22%, night: 48%), and GBF (day: 96%, night: 147%), demonstrating that an overall cardiorespiratory upregulation occurs during seawater acclimation. The elevated GBF was achieved via a combination of increased CO, mediated through elevated stroke volume (SV), and a redistribution of blood flow to the gastrointestinal tract. Interestingly, virtually all of the increase in CO of seawater-acclimated trout was directed to the gastrointestinal tract. Although unfed seawater-acclimated trout displayed substantially elevated cardiorespiratory activity, the ingestion of a meal resulted in a similar specific dynamic action (SDA) and postprandial GBF response as in freshwater-acclimated fish. This indicates that the capacity for the transportation of absorbed nutrients, gastrointestinal tissue oxygen delivery, and acid-base regulation is maintained during digestion in seawater. The novel findings presented in this study clearly demonstrate that euryhaline fish upregulate cardiovascular function when in seawater, while retaining sufficient capacity for the metabolic and cardiovascular changes associated with the postprandial response.
Ämne (baseras på Högskoleverkets indelning av forskningsämnen):
NATURVETENSKAP ->
Biologiska vetenskaper ->
Zoologi ->
Zoofysiologi
Nyckelord:
saltwater, gut blood flow, cardiovascular, feeding, metabolic rate, ACID-BASE REGULATION, GUT BLOOD-FLOW, ONCORHYNCHUS-MYKISS, FRESH-WATER, OXYGEN-CONSUMPTION, SALMO-GAIRDNERI, ALKALINE TIDE, BICARBONATE, SECRETION, METABOLIC-RESPONSE, DYNAMIC ACTION
Postens nummer:
238627
Posten skapad:
2016-06-29 13:04

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