The endocrine regulation of hydromineral balance in aquatic vertebrates

作为一名比较生理学家/内分泌学家，我对动物如何“工作”很感兴趣。我的研究重点是内分泌系统如何调节鱼类等水生脊椎动物的盐分和水分平衡。像所有动物一样，鱼类必须保持“内稳态”(即体内稳定)。当循环中的盐(即离子)水平失衡时，无论是由于环境条件的自然变化还是由于环境干扰，内分泌系统都会调节体内平衡的恢复。这是通过荷尔蒙对组织的作用来调节动物身体和周围环境之间的水和盐的转移而发生的。这些组织包括肾脏、胃肠道和皮肤。在鱼类中，鳃也特别重要，因为它们直接与周围的水接触。这些组织被称为上皮细胞，它们各自建立了一个屏障，将两个液体隔开。在鳃的情况下，这两个隔间是身体和周围的水。上皮组织调节离子和水在细胞内(跨细胞)或细胞间(细胞旁)的移动。虽然已经进行了大量的研究来了解离子在细胞间的移动，但很少有人研究是什么调节了离子在细胞之间的移动。这是令人惊讶的，因为细胞旁通路的通透性是由紧密连接(TJ)复合体控制的，TJ在所有脊椎动物的一般生理学中都被广泛认为是非常重要的。在接下来的拨款周期中，我的工作将集中于更好地了解调节鱼类TJ渗透性的“机制”，以及内分泌系统是如何控制TJ的。在NSERC的支持下，我已经证明了组成TJ复合体的一些蛋白质对环境变化非常敏感，我假设TJ蛋白质在水生生物的总体福祉以及最终我们的水生生态系统中发挥着极其重要的作用。

As a comparative physiologist/endocrinologist, I am interested in how animals "work". My research program is focused on how the endocrine system regulates salt and water balance in aquatic vertebrates such as fishes. Like all animals, fishes must maintain "homeostasis" (i.e. internal stability). When circulating salt (i.e. ion) levels are out of balance, either through natural alterations in environmental conditions or through environmental disturbance, the endocrine system regulates the reinstatement of homeostasis. This occurs through the action of hormones on tissues that regulate the transfer of water and salt between the animal body and the surrounding environment. These tissues include the kidney, gastrointestinal tract and skin. In fishes, the gills are also particularly important because they directly interface with surrounding water. These aforementioned tissues are referred to as epithelia and they each establish a barrier that separates two fluid compartments. In the case of the gill, these two compartments are the body and the surrounding water. Epithelial tissue regulates the movement of ions and water either across the cells (transcellular) or between the cells (paracellular). While a lot of research has been conducted in order to understand the movement of ions across cells, very little has been done in order to understand what regulates the movement of ions between cells. This is surprising because the permeability of the paracellular route is controlled by the tight junction (TJ) complex and TJs are widely acknowledged to be very important in the general physiology of all vertebrate organisms. My work over the coming grant cycle will focus on gaining a much better understanding of the "machinery" that regulates the permeability of the TJ in fishes and how it is controlled by the endocrine system. With NSERC support I have already demonstrated that some of the proteins that comprise the TJ complex are very sensitive to environmental change and I hypothesize that TJ proteins play an extremely important role in the general well-being of aquatic organisms and ultimately our aquatic ecosystems.