Physiological responses to air exposure: acid-base balance and the role of branchial water stores
Physiological responses to air exposure: acid-base balance and the role of branchial water stores
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对空气暴露的生理反应：酸碱平衡和鳃水储存的作用
DOI：
10.1093/icb/28.1.125
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发表时间：
1988
影响因子：
2.6
通讯作者：
L. Burnett
中科院分区：
文献类型：
--
作者：
L. Burnett
概要。当潮间带生物暴露在空气中时，它们通常表现出两种行为之一。它们要么与空中环境隔离，要么与空中环境相互作用。在使用第一种行为的动物中，体液酸碱平衡部分地通过溶解双壳软体动物中的碳酸钙壳来维持，以缓冲厌氧产生的代谢酸。钙离子通过增加强离子差来补偿酸中毒。碳酸盐从外壳中释放会导致分子CO2的增加，这在一定程度上抵消了补偿，但通过将CO2分配到外壳内的其他流体中和/或将外壳排放到空气中，可以将这种影响降至最低。在具有相当高浓度的呼吸色素的动物中，如沙蚕，厌氧诱导的酸中毒通过大的Haldalone效应而最小化。在与空气环境相互作用的动物中，十足类甲壳动物大体上维持其有氧代谢，尽管它可能大大减少。由于血淋巴Pco 2升高引起的呼吸性酸中毒可能完全代偿或完全不代偿。补偿包括血淋巴钙的增加，可能来自碳酸钙外骨骼。补偿机制还可以包括积累可滴定碱的鳃储水器。有人建议，碱化的鳃水保持一个陡峭的PCO 2梯度横跨鳃，并减少了酸中毒的幅度很短的一段时间。以这种方式使用鳃贮水的能力可能与动物的水调节能力有关。
SYNOPSIS. Intertidal organisms usually exhibit one of two behaviors when they are air exposed. They either isolate themselves from the aerial environment or they interact with the aerial environment. Among the animals using the first behavior, body fluid acid-base balance is partially maintained by dissolution of the calcium carbonate shell in the bivalve molluscs to buffer the metabolic acids produced anaerobically. Calcium ions compensate for the acidosis by increasing the strong ion difference. The release of carbonate from the shell causes an increase in molecular CO2 which offsets the compensation somewhat, but this effect is minimized by distributing the CO2 among the other fluids within the shell and/or by venting the shell to the air. In animals which have a fairly high concentration of a respiratory pigment, such as a lugworm, an anaerobically induced acidosis is minimized by a large Haldane effect. Among the animals which interact with the aerial environment, the decapod crustaceans by and large maintain their metabolism aerobically, although it may be greatly reduced. A respiratory acidosis due to elevated hemolymph Pco2 may be either fully compensated or not at all. Compensation involves an increase in hemolymph calcium, probably from the calcium carbonate exoskeleton. Compensatory mechanisms may also include branchial water stores which accumulate a titratable base. It is suggested that the alkalinization of the branchial water maintains a steeper Pco2 gradient across the gill and reduces the magnitude of the acidosis for a short period of time. The ability to use branchial water stores in this way may be tied to the ability of the animal to osmoregulate.