White sturgeon (Acipenser transmontanus) acid-base regulation differs in response to different types of acidoses.

White sturgeon (Acipenser transmontanus) completely protect intracellular tissue pH (pH) despite large reductions in extracellular (blood) pH (pH), termed preferential pH regulation, in response to elevated environmental PCO (hypercarbia) and in general appear to be relatively resilient to stressors. Preferential pH regulation is thought to be associated with hypercarbia tolerance in general, but has also recently been observed to protect pH against metabolic acidoses induced by exhaustive exercise and anoxia in a tropical air breathing catfish. We hypothesized that preferential pH regulation may also be a general strategy of acid-base regulation in sturgeon.

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

Migratory 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.

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

Migratory 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 iono- and acid-base regulation.