Fish aquaculture facilities strive to maintain abiotic conditions that optimise somatic growth. Two physiological systems that are critically linked to environmental abiotic factors are ion and acid-base regulation. Given the detrimental effects of ionic and acid-base imbalances coupled with the potential energetic costs of ion and acid-base regulation, it is important to understand how changes in abiotic variables such as salinity, temperature and pH alter ionoregulatory and acid-base physiology. The gill is the predominant site of ion and acid-base regulation, two linked processes that are vital to the health of fishes. Most species maintain ion levels in the blood plasma within a narrow range, independent of external ion concentrations. In freshwater (FW), fishes must actively take up ions from their dilute environment to counteract passive ion losses, while in seawater (SW), ion excretion serves to counteract passive salt gain. Ion uptake (FW) and excretion (SW) are coordinated by different subtypes of ion-transporting cells (ionocytes) expressed in the gill epithelium. In this review, we discuss the function of FW and SW ionocytes in the movement of ions across the gill epithelium and address other features of the gill that are integral to ionoregulation. We also discuss the mechanisms of acid-base regulation by the gill, which is intimately related to ion regulation because it is coordinated by Na⁺- and Cl⁻-linked fluxes of acid (H⁺) and base (HCO−3${\text{HCO}}_3^{-}$${\text{HCO}}_3^{-}$) equivalents. These fundamental physiological principles are integral in understanding how fishes in aquaculture respond to relevant disturbances that may occur under culture conditions.

中文翻译：

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生理学和水产养殖：鱼类鳃离子和酸碱调节的综述

鱼类养殖设施努力维持优化体细胞生长的非生物条件。与环境非生物因素密切相关的两个生理系统是离子和酸碱调节。鉴于离子和酸碱失衡的不利影响，以及离子和酸碱调节的潜在能量成本，了解盐度、温度和 pH 等非生物变量的变化如何改变离子调节和酸碱生理学非常重要。鳃是离子和酸碱调节的主要场所，这两个过程对鱼类的健康至关重要。大多数物种将血浆中的离子水平维持在一个狭窄的范围内，与外部离子浓度无关。在淡水 (FW) 中，鱼类必须主动从稀释环境中吸收离子以抵消被动离子损失，而在海水 (SW) 中，离子排泄用于抵消被动盐分增加。离子摄取 (FW) 和排泄 (SW) 由鳃上皮中表达的不同亚型离子转运细胞 (离子细胞) 协调。在这篇综述中，我们讨论了 FW 和 SW 离子细胞在离子穿过鳃上皮细胞运动中的功能，并讨论了与离子调节有关的其他鳃特征。我们还讨论了鳃调节酸碱的机制，这与离子调节密切相关，因为它是由 Na 协调的。离子摄取 (FW) 和排泄 (SW) 由鳃上皮中表达的不同亚型离子转运细胞 (离子细胞) 协调。在这篇综述中，我们讨论了 FW 和 SW 离子细胞在离子穿过鳃上皮细胞运动中的功能，并讨论了与离子调节有关的其他鳃特征。我们还讨论了鳃调节酸碱的机制，这与离子调节密切相关，因为它是由 Na 协调的。离子摄取 (FW) 和排泄 (SW) 由鳃上皮中表达的不同亚型离子转运细胞 (离子细胞) 协调。在这篇综述中，我们讨论了 FW 和 SW 离子细胞在离子穿过鳃上皮细胞运动中的功能，并讨论了与离子调节有关的其他鳃特征。我们还讨论了鳃调节酸碱的机制，这与离子调节密切相关，因为它是由 Na 协调的。⁺ - 和 Cl ^{- -}酸 (H ⁺ ) 和碱 (碳酸氢钠-3${\text{碳酸氢钠}}_3^{-}$${\text{HCO}}_3^{-}$) 等价物。这些基本生理原理对于理解水产养殖中的鱼类如何应对养殖条件下可能发生的相关干扰是不可或缺的。