Programme for Physiology and Neurobiology, Department of Molecular Biosciences, University of Oslo, Oslo, Norway.
Respir Physiol Neurobiol. 2012 Dec 1;184(3):214-22. doi: 10.1016/j.resp.2012.07.012. Epub 2012 Jul 27.
The ability of some fishes to reversibly remodel their gill morphology has become a focus of research after the discovery of extreme morphological gill plasticity in crucian carp and goldfish-both members of the cyprinid genus Carassius. Their lamellae are largely embedded in an interlamellar cell mass (ILCM) during normoxic conditions in cold water. The ILCM regresses in hypoxia, warm water, and during exercise, whereby the respiratory surface area and the capacity for oxygen uptake are greatly increased. There may be several reasons for covering the lamellae when oxygen needs are low. Reducing osmoregulatory costs have been suggested as an advantage of gill remodeling, but this has been difficult to show, putting the importance of the osmo-respiratory compromise into question. Other reasons could be to limit uptake of toxic substances and to reduce the risks for infections. In support for the latter, we present evidence showing that crucian carp infected by gill flukes maintain their ILCM when exposed to hypoxia. So far, gill remodeling in response to oxygen needs has been seen in several cyprinids, killifish and eel. In response to other environmental factors it may also occur in salmonids and anabantoids, revealing a phylogenetically widespread occurrence among teleosts.
在发现鲫鱼和金鱼（均属于鲤鱼属 Carassius）具有极端形态的鳃可塑性后，一些鱼类能够可逆地重塑其鳃形态的能力成为了研究的焦点。在冷水的常氧条件下，它们的鳃片在细胞间基质（ILCM）中大部分被嵌入。ILCM 在低氧、温水和运动期间退化，从而大大增加了呼吸表面积和氧气摄取能力。当氧气需求较低时，覆盖鳃片可能有几个原因。有人认为，减少渗透压调节成本是鳃重塑的一个优势，但这很难证明，因此对渗透压和呼吸之间的权衡的重要性提出了质疑。其他原因可能是限制有毒物质的摄取并降低感染的风险。为了支持后者，我们提供了证据表明，鲫鱼在受到低氧时会保持其 ILCM，尽管受到了鳃吸虫的感染。到目前为止，已经在几种鲤鱼、食蚊鱼和鳗鱼中观察到了对氧气需求的鳃重塑。为了应对其他环境因素，鲑鱼和攀鲈科鱼类也可能会发生鳃重塑，这表明硬骨鱼中的鳃重塑是广泛存在的。
