Rapid and reversible modulation of blood haemoglobin content during diel cycles of hypoxia in killifish (Fundulus heteroclitus)

Borowiec, Brittney G.; Scott, Graham R.

doi:10.1016/j.cbpa.2021.111054

Cited by 6 publications

(1 citation statement)

References 55 publications

(69 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dynamic increases in capillary haematocrit and erythrocyte flow through capillaries are particularly important for augmenting O 2 transport to muscles during exercise in mammals (Poole, 2019), though the regulation of erythrocyte flow through capillaries during hypoxia and in fish in general is poorly understood. These increases in blood haemoglobin content in the fluctuating group at warm temperature are too rapid to be caused by erythropoiesis, and are likely attributable to splenic contraction, which is known to enable rapid modulation of blood haemoglobin content in killifish and many other species (Borowiec and Scott, 2021;Fänge and Nilsson, 1985;Lai et al, 2006;Yamamoto, 1987;Yamamoto et al, 1985). Increases in haemoglobin-O 2 affinity may also help improve hypoxia tolerance across temperatures, based on the significant effect of acclimation group on P 50 that was driven by lower P 50 values in the fluctuating group (Fig.…”

Section: Discussionmentioning

confidence: 99%

Constant temperature and fluctuating temperature have distinct effects on hypoxia tolerance in killifish (Fundulus heteroclitus)

Ridgway

Scott

2023

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

Climate change is leading to rapid change in aquatic environments, increasing the mean and variability of temperatures, and increasing the incidence of hypoxia. We investigated how acclimation to constant temperatures or to diel temperature fluctuations affect hypoxia tolerance in mummichog killifish (Fundulus heteroclitus). Killifish were acclimated to constant cool (15˚C), constant warm (25˚C), or a diel temperature cycle (15˚C at night, 25˚C during day) for 6 weeks. We then measured hypoxia tolerance (time to loss of equilibrium in severe hypoxia, tLOE; critical O2 tension, Pcrit), whole-animal metabolism, gill morphology, haematology, and tissue metabolites at 15˚C and 25˚C in a full factorial design. Among constant temperature groups, tLOE was highest and Pcrit was lowest in fish tested at their acclimation temperature. Warm acclimated fish had lower metabolic rate at 25˚C and greater gill surface area (less coverage of lamellae by interlamellar cell mass, ILCM), but cool acclimated fish had greater brain glycogen stores. Therefore, effects of constant temperature acclimation on hypoxia tolerance were temperature specific and not exhibited broadly across test temperatures, and they were associated with different underlying mechanisms. Hypoxia tolerance was less sensitive to test temperature in fish acclimated to fluctuating temperatures compared to fish acclimated to constant temperature. Acclimation to fluctuating temperatures also increased haemoglobin-O2 affinity of the blood (decreased P50) compared to constant temperature groups. Therefore, acclimation to fluctuating temperatures helps maintain hypoxia tolerance across a broader range of temperatures, and leads to some distinct physiological adjustments that are not exhibited by fish acclimated to constant temperatures.

show abstract

Section: Discussionmentioning

confidence: 99%

Constant temperature and fluctuating temperature have distinct effects on hypoxia tolerance in killifish (Fundulus heteroclitus)

Ridgway

Scott

2023

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

show abstract

Response signatures of intestinal microbiota and gene transcription of the tiger grouper Epinephelus fuscoguttatus to nervous necrosis virus infection

et al. 2022

View full text Add to dashboard Cite

Physiological and behavioural strategies of aquatic animals living in fluctuating environments

Blewett

Binning

Weinrauch

et al. 2022

Journal of Experimental Biology

View full text Add to dashboard Cite

Shallow or near-shore environments, such as ponds, estuaries and intertidal zones, are among the most physiologically challenging of all aquatic settings. Animals inhabiting these environments experience conditions that fluctuate markedly over relatively short temporal and spatial scales. Living in these habitats requires the ability to tolerate the physiological disturbances incurred by these environmental fluctuations. This tolerance is achieved through a suite of physiological and behavioural responses that allow animals to maintain homeostasis, including the ability to dynamically modulate their physiology through reversible phenotypic plasticity. However, maintaining the plasticity to adjust to some stresses in a dynamic environment may trade off with the capacity to deal with other stressors. This paper will explore studies on select fishes and invertebrates exposed to fluctuations in dissolved oxygen, salinity and pH. We assess the physiological mechanisms these species employ to achieve homeostasis, with a focus on the plasticity of their responses, and consider the resulting physiological trade-offs in function. Finally, we discuss additional factors that may influence organismal responses to fluctuating environments, such as the presence of multiple stressors, including parasites. We echo recent calls from experimental biologists to consider physiological responses to life in naturally fluctuating environments, not only because they are interesting in their own right but also because they can reveal mechanisms that may be crucial for living with increasing environmental instability as a consequence of climate change.

show abstract

Rapid and reversible modulation of blood haemoglobin content during diel cycles of hypoxia in killifish (Fundulus heteroclitus)

Cited by 6 publications

References 55 publications

Constant temperature and fluctuating temperature have distinct effects on hypoxia tolerance in killifish (Fundulus heteroclitus)

Constant temperature and fluctuating temperature have distinct effects on hypoxia tolerance in killifish (Fundulus heteroclitus)

Response signatures of intestinal microbiota and gene transcription of the tiger grouper Epinephelus fuscoguttatus to nervous necrosis virus infection

Physiological and behavioural strategies of aquatic animals living in fluctuating environments

Contact Info

Product

Resources

About