Supplementary material from "Functional support for a novel mechanism that enhances tissue oxygen extraction in a teleost fish"
A successful spawning migration in salmon depends on their athletic ability, and thus, on efficient cardiovascular oxygen (O 2 ) transport. Most teleost fishes have highly pH-sensitive haemoglobins (Hb) that can release large amounts of O 2 when the blood is acidified at the tissues. We hypothesized...
| Main Authors: | , , , , |
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| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
Figshare
2019
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| Subjects: | |
| Online Access: | https://dx.doi.org/10.6084/m9.figshare.c.4508273.v1 https://rs.figshare.com/collections/Supplementary_material_from_Functional_support_for_a_novel_mechanism_that_enhances_tissue_oxygen_extraction_in_a_teleost_fish_/4508273/1 |
| Summary: | A successful spawning migration in salmon depends on their athletic ability, and thus, on efficient cardiovascular oxygen (O 2 ) transport. Most teleost fishes have highly pH-sensitive haemoglobins (Hb) that can release large amounts of O 2 when the blood is acidified at the tissues. We hypothesized that plasma-accessible carbonic anhydrase (paCA; the enzyme that catalyses proton production from CO 2 ) is required to acidify the blood at the tissues and promote tissue O 2 extraction. Previous studies have reported an elevated tissue O 2 extraction in hypoxia-acclimated teleosts that may also be facilitated by paCA. Thus, to create experimental contrasts in tissue O 2 extraction, Atlantic salmon were acclimated to normoxia or hypoxia (40% air saturation, greater than six weeks), and the role of paCA in enhancing tissue O 2 extraction was tested by inhibiting paCA at rest and during submaximal exercise. Our results show that: (i) in both acclimation groups, the inhibition of paCA increased cardiac output by one-third, indicating a role of paCA in promoting tissue O 2 extraction during exercise, recovery and at rest; (ii) the recruitment of paCA was plastic and increased following hypoxic acclimation; and (iii) maximal exercise performance in salmon, and thus a successful spawning migration, may not be possible without paCA. |
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