Patterns of Acid–Base Regulation During Exposure to Hypercarbia in Fishes

Brauner, C.J.; Baker, Daniel W.

doi:10.1007/978-3-540-93985-6_3

Cited by 91 publications

(131 citation statements)

References 56 publications

Supporting

Mentioning

125

Contrasting

Order By: Relevance

“…Thus, the armored catfish Liposarcus pardalis only recovered 8% and 22% of the pH e disturbance when exposed to ∼7 mmHg CO 2 and 42 mmHg CO 2 , respectively for 96 h (Brauner et al, 2004). Similarly, the bowfin Amia calva regulated 28% and 24% of the pH e disturbance at 11 and 45 mmHg CO 2 , respectively, after 24 h (Brauner and Baker, 2009) and Arapaima gigas only partly compensated the pH e disturbance incurred after exposure to 40 mmHg CO 2 for 72 h (Gonzalez et al, 2010). No indication of extracellular acid-base regulation was detected in the South American lungfish (Lepidosiren paradoxa) over 50 h at 49 mmHg CO 2 (Sanchez et al, 2005).…”

Section: Results and Discussion Acid-base Regulation During Hypercapniamentioning

confidence: 92%

“…However, the gills of airbreathing fishes are generally reduced in size -an adaptation that is presumed to aid in avoiding branchial O 2 loss in hypoxic water -but have retained their ancestral function in acid-base and ion regulation (Graham, 1997;Tamura and Moriyama, 1976). It has therefore been suggested that the reduced surface area of the gills of air-breathing fishes places limitations on transepithelial ion exchange, thus constraining the branchial capacity for acid-base regulation (Brauner and Baker, 2009;Shartau and Brauner, 2014). Therefore, all studies on acid-base regulation in air-breathing fishes to date indicate a low capacity for exchange of acid-base equivalents in pH e regulation and a preferential regulation of intracellular pH, during a respiratory acidosis (Brauner and Baker, 2009;Brauner et al, 2004;Harter et al, 2014b;Heisler, 1982;Shartau and Brauner, 2014).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High capacity for extracellular acid-base regulation in the air-breathing fishPangasianodon hypophthalmus

Damsgaard

Gam

Tuong

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

The evolution of accessory air-breathing structures is typically associated with reduction of the gills, although branchial ion transport remains pivotal for acid-base and ion regulation. Therefore, airbreathing fishes are believed to have a low capacity for extracellular pH regulation during a respiratory acidosis. In the present study, we investigated acid-base regulation during hypercapnia in the airbreathing fish Pangasianodon hypophthalmus in normoxic and hypoxic water at 28-30°C. Contrary to previous studies, we show that this air-breathing fish has a pronounced ability to regulate extracellular pH (pH e ) during hypercapnia, with complete metabolic compensation of pH e within 72 h of exposure to hypoxic hypercapnia with CO 2 levels above 34 mmHg. The high capacity for pH e regulation relies on a pronounced ability to increase levels of HCO 3 − in the plasma. Our study illustrates the diversity in the physiology of air-breathing fishes, such that generalizations across phylogenies may be difficult.

show abstract

Section: Results and Discussion Acid-base Regulation During Hypercapniamentioning

confidence: 92%

Section: Introductionmentioning

confidence: 99%

High capacity for extracellular acid-base regulation in the air-breathing fishPangasianodon hypophthalmus

Damsgaard

Gam

Tuong

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

show abstract

“…To place our study in a broader perspective, various authors (Heisler 1986;Ultsch 1996;Brauner and Baker 2009) have suggested that aquatic hypercarbia has been underestimated as a selective pressure associated with a number of important vertebrate adaptations. Among fishes, white sturgeon display an exceptional tolerance to hypercapnia, and this tolerance extends to cardiac performance.…”

Section: Discussionmentioning

confidence: 99%

“…For most fishes, short-term exposure to a P w co 2 of more than 2 kPa results in uncompensated acidosis (see Brauner and Baker 2009) that can be lethal, although the exact mechanism(s) of CO 2 toxicity are unknown (Putnam and Roos 1997). In contrast, white sturgeon Acipenser transmontanus are remarkably tolerant of elevated CO 2 and the associated blood acidosis, exhibiting morbidity only when exposed to ≥8-kPa P w co 2 (D. W. Baker and C. J.…”

Section: Introductionmentioning

confidence: 99%

Exceptional CO₂Tolerance in White Sturgeon (Acipenser transmontanus) Is Associated with Protection of Maximum Cardiac Performance during Hypercapnia In Situ

Baker¹,

Hanson²,

Farrell³

et al. 2011

Physiological and Biochemical Zoology

View full text Add to dashboard Cite

This is an electronic version of an article that was published as: Baker, D.W., Hanson, L.M., Farrell, A.P., & Brauner, C.J. (2011). Exceptional CO2 tolerance in white sturgeon (Acipenser transmontanus) is associated with protection of maximum cardiac performance during hypercapnia in situ. ABSTRACTWhite sturgeon rank among the most CO 2 -tolerant fish species examined to date. We investigated whether this exceptional CO 2 tolerance extended to the heart, an organ generally viewed as acidosis intolerant. Maximum cardiac output (Q max ) and maximum cardiac power output (PO max ) were assessed using a working, perfused, in situ heart preparation. Exposure to a Pco 2 of 3 kPa for 20 min had no significant effect on maximum cardiac performance, while exposure to 6-kPa Pco 2 reduced heart rate, Q max , PO max , and rate of ventricular force generation (F O ) by 23%, 28%, 26%, and 18%, respectively; however, full recovery was observed in all these parameters upon return to control conditions. These modest impairments during exposure to 6-kPa Pco 2 were associated with partially compensated intracellular ventricular acidosis. Maximum adrenergic stimulation (500 nmol L Ϫ1 adrenaline) during 6-kPa Pco 2 protected maximum cardiac performance via increased inotropy (force of contraction) without affecting heart rate. Exposure to higher CO 2 levels associated with morbidity in vivo (i.e., 8-kPa Pco 2 ) induced arrhythmia and a reduction in stroke volume during power assessment. Clearly, white sturgeon hearts are able to increase cardiac performance during severe hypercapnia that is lethal to other fishes. Future work focusing on atypical aspects of sturgeon cardiac function, including the lack of chronotropic response to adrenergic stimulation during hypercapnia, is warranted.

show abstract

“…or anthropogenic stimuli (Heisler, 1982;Ultsch, 1996;Burnett, 1997). Exposure of water-breathing fishes to aquatic hypercarbia can cause a reduction in blood pH ( pH e ), which results in a respiratory acidosis (reviewed by Brauner and Baker, 2009). Characterizing how the seaward migration made by anadromous fishes is affected by hypercarbia may become even more relevant in the near future as anthropogenic P CO2 in both marine (Caldeira and Wickett, 2003) and freshwater (Sayer et al, 1993) systems increase.…”

Section: Introductionmentioning

confidence: 99%

Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity

Shaughnessy¹,

Baker²,

Brauner³

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

, J.S. (2015). Interaction of osmoregulatory and acidbase compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity. The Journal of Experimental Biology, 218(17), 2712 -2719 . DOI: 10.1242 The Journal of Experimental Biology is published by The Company of Biologists. More information about the journal can be found at: http://jeb.biologists.org/. This article can be accessed at: http://dx.doi.org/10.1242/jeb.125567. RESEARCH ARTICLEInteraction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity ABSTRACTMigratory fishes encounter a variety of environmental conditions, including changes in salinity, temperature and dissolved gases, and it is important to understand how these fishes are able to acclimate to multiple environmental stressors. The gill is the primary site of both acid-base balance and ion regulation in fishes. Many ion transport mechanisms involved with acid-base compensation are also required for the regulation of plasma Na + and Cl + , the predominant extracellular ions, potentially resulting in a strong interaction between ionoregulation and acid-base regulation. The present study examined the physiological interaction of elevated dissolved CO 2 (an acid-base disturbance) on osmoregulation during seawater acclimation (an ionoregulatory disturbance) in juvenile white sturgeon (Acipenser transmontanus). Blood pH ( pH e ), plasma [ (NKCC) abundance were examined over a 10 day seawater (SW) acclimation period under normocarbia (NCSW) or during prior and continued exposure to hypercarbia (HCSW), and compared with a normocarbic freshwater (NCFW) control. Hypercarbia induced a severe extracellular acidosis (from pH 7.65 to pH 7.2) in HCSW sturgeon, and these fish had a 2-fold greater rise in plasma osmolarity over NCSW by day 2 of SW exposure. Interestingly, pH e recovery in HCSW was associated more prominently with an elevation in plasma Na + prior to osmotic recovery and more prominently with a reduction in plasma Cl − following osmotic recovery, indicating a biphasic response as the requirements of osmoregulation transitioned from ion-uptake to ion-excretion throughout SW acclimation. These results imply a prioritization of osmoregulatory recovery over acid-base recovery in this period of combined exposure to acid-base and ionoregulatory disturbances.KEY WORDS: Osmoregulation, Acid-base balance, Seawater, Hypercarbia, Multiple stressors INTRODUCTIONAlthough there is a great deal known about how fishes acclimate to environmental stressors in isolation (such as acclimating to changes in salinity: reviewed by Evans et al., 1999;Marshall and Grosell, 2005), much less is known about how fishes respond to multiple, potentially interacting, environmental stressors. For instance, it is not well understood in any anadromous fishes how ion and water balance during salinity acclimation are affected by other environmental stressors likely encountered during ...

show abstract

Patterns of Acid–Base Regulation During Exposure to Hypercarbia in Fishes

Cited by 91 publications

References 56 publications

High capacity for extracellular acid-base regulation in the air-breathing fishPangasianodon hypophthalmus

High capacity for extracellular acid-base regulation in the air-breathing fishPangasianodon hypophthalmus

Exceptional CO₂Tolerance in White Sturgeon (Acipenser transmontanus) Is Associated with Protection of Maximum Cardiac Performance during Hypercapnia In Situ

Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity

Contact Info

Product

Resources

About

Patterns of Acid–Base Regulation During Exposure to Hypercarbia in Fishes

Cited by 91 publications

References 56 publications

High capacity for extracellular acid-base regulation in the air-breathing fishPangasianodon hypophthalmus

High capacity for extracellular acid-base regulation in the air-breathing fishPangasianodon hypophthalmus

Exceptional CO2Tolerance in White Sturgeon (Acipenser transmontanus) Is Associated with Protection of Maximum Cardiac Performance during Hypercapnia In Situ

Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity

Contact Info

Product

Resources

About

Exceptional CO₂Tolerance in White Sturgeon (Acipenser transmontanus) Is Associated with Protection of Maximum Cardiac Performance during Hypercapnia In Situ