Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP, Instituto de Biociências, Campus do Litoral Paulista, Praça Infante Dom Henrique, s/n, Parque Bitaru, São Vicente, SP, CEP 11330-900, Brazil.
Centro de Aquicultura da UNESP/CAUNESP, Via de Acesso Professor Paulo Donato Castellane, s/n, Jaboticabal, SP, CEP 14484-900, Brazil.
J Comp Physiol B. 2018 Sep;188(5):729-738. doi: 10.1007/s00360-018-1167-0. Epub 2018 Jun 11.
Survival, osmoregulatory pattern, oxygen consumption, energy spent on metabolism, ammonia excretion, type of oxidized energy substrate, and hepatosomatic index were evaluated in decapods (an osmoregulating crab, Callinectes danae, and an osmoconforming seabob shrimp, Xiphopenaeus kroyeri) exposed to carbon dioxide-induced water acidification (pH 7.3, control pH 8.0) and different salinities (20, 25, 30, 35, and 40‰) for 3 days. Compared to the animals kept at controlled pH, exposure to reduced pH resulted in the loss of osmoregulatory capacity in C. danae at all salinities, except for some hyporegulation at 40‰, and reduced oxygen consumption and ammonia excretion at 20 and 40‰. Xiphopenaeus kroyeri remained an osmoconformer in all evaluated conditions, except for some hyporegulation at 40‰, and when exposed to the reduced pH, it presented changes in oxygen consumption at all salinities and reductions in ammonia excretion at 20 and 35‰ compared to the control animals. Both species use protein as the main energy substrate and decrease the hepatosomatic index when exposed to reduced pH relative to the control. The observed changes may be associated with changes in the activity of enzymes related to osmoregulation, the use of amino acids as osmotic effectors of cell volume control and recovery, and the Bohr effect, and, because the gills are multifunctional organs related to osmoregulation, the changes may be related to acid-base control, nitrogen excretion, and respiration, with a change in one of these functions bringing about changes in the others.
生存、渗透调节模式、耗氧量、代谢消耗的能量、氨排泄、氧化能量底物的类型以及肝体指数，在暴露于二氧化碳引起的水酸化（pH7.3，对照 pH8.0）和不同盐度（20、25、30、35 和 40‰）3 天后，对十足目动物（一种渗透压调节蟹 Callinectes danae 和一种渗透调节海鳌虾 Xiphopenaeus kroyeri）进行了评估。与在对照 pH 下饲养的动物相比，在所有盐度下，暴露于降低的 pH 值会导致 C.danae 失去渗透调节能力，除了在 40‰时有些低渗调节外，还会降低耗氧量和氨排泄。Xiphopenaeus kroyeri 在所有评估条件下仍保持渗透调节，除了在 40‰时有些低渗调节外，当暴露于降低的 pH 值时，在所有盐度下都会改变耗氧量，并在 20 和 35‰时降低氨排泄，与对照动物相比。这两个物种都将蛋白质用作主要能量底物，并且与对照相比，当暴露于降低的 pH 值时，肝体指数会降低。观察到的变化可能与与渗透压调节相关的酶活性变化、氨基酸作为细胞体积控制和恢复的渗透效应物的利用以及 Bohr 效应有关，并且由于鳃是与渗透压调节相关的多功能器官，这些变化可能与酸碱控制、氮排泄和呼吸有关，其中一种功能的变化会导致其他功能的变化。
