Kato Akira, Nagashima Ayumi, Hosono Kohei, Romero Michael F
School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan.
Department of Physiology and Biomedical Engineering, Nephrology and Hypertension and O'Brien Urology Research Center, Mayo Clinic College of Medicine & Science, Rochester, MN, United States.
Front Physiol. 2022 Jun 23;13:939114. doi: 10.3389/fphys.2022.939114. eCollection 2022.
The kidney is an important organ that maintains body fluid homeostasis in seawater and freshwater teleost fishes. Seawater teleosts excrete sulfate and magnesium in small amounts of isotonic urine, and freshwater teleosts excrete water in large amounts of hypo-osmotic urine. The volume, osmolality, and ionic compositions of the urine are regulated mainly by membrane transport proteins expressed in the renal tubular epithelial cells. Gene expression, immunohistochemical, and functional analyses of the fish kidney identified membrane transport proteins involved in the secretion of sulfate and magnesium ions by the proximal tubules and reduction of urine volume by the collecting ducts in seawater teleosts, and excretion of water as hypotonic urine by the distal tubules and collecting ducts in freshwater teleosts. These studies promote an understanding of how the kidney contributes to the seawater and freshwater acclimation of teleosts at the molecular level.
肾脏是维持海水和淡水硬骨鱼类体液平衡的重要器官。海水硬骨鱼通过排出少量等渗尿液来排泄硫酸盐和镁，而淡水硬骨鱼则通过排出大量低渗尿液来排水。尿液的体积、渗透压和离子组成主要由肾小管上皮细胞中表达的膜转运蛋白调节。对鱼类肾脏的基因表达、免疫组织化学和功能分析确定了参与海水硬骨鱼近端小管分泌硫酸盐和镁离子以及集合管减少尿量的膜转运蛋白，以及淡水硬骨鱼远端小管和集合管排出低渗尿液的膜转运蛋白。这些研究有助于在分子水平上理解肾脏如何促进硬骨鱼对海水和淡水的适应。
