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。我的研究方向是鱼类等水生脊椎动物的内分泌系统如何调节盐和水的平衡。像所有动物一样，鱼类必须保持“体内平衡”（即内部稳定）。当循环盐（即离子）水平由于环境条件的自然改变或环境干扰而失去平衡时，内分泌系统调节体内平衡的恢复。这是通过激素对组织的作用来实现的，这些组织调节着动物身体和周围环境之间水和盐的转移。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。上述组织被称为上皮细胞，它们各自建立一个屏障，将两个液体隔室分开。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（旁细胞）的运动。虽然为了了解离子在细胞间的运动已经进行了大量的研究，但为了了解是什么调节了细胞间离子的运动，所做的研究却很少。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）复合物控制的，而TJ在所有脊椎动物的一般生理中被广泛认为是非常重要的。在接下来的拨款周期中，我的工作将集中在更好地理解调节鱼类TJ通透性的“机制”以及它是如何被内分泌系统控制的。在NSERC的支持下，我已经证明了组成TJ复合物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健康中起着极其重要的作用，最终我们的水生生态系统。

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.