The urothelium, which lines the renal pelvis, ureters, urinary bladder, and proximal urethra, forms a high resistance but adaptable barrier that surveils its mechanochemical environment and communicates changes to underlying tissues including afferent nerve fibers and the smooth muscle. The goal of this review is to summarize new insights into urothelial biology and function that have occurred in the past decade. After familiarizing the reader with key aspects of urothelial histology, we describe new insights into urothelial development and regeneration. This is followed by an extended discussion of urothelial barrier function, including information about the roles of the glycocalyx, ion and water transport, tight junctions, and the cellular and tissue shape changes and other adaptations that accompany expansion and contraction of the lower urinary tract. We also explore evidence that the urothelium can alter the water and solute composition of urine during normal physiology and in response to overdistension. We complete the review by providing an overview of our current knowledge about the urothelial environment, discussing the sensor and transducer functions of the urothelium, exploring the role of circadian rhythms in urothelial gene expression, and describing novel research tools that are likely to further advance our understanding of urothelial biology.

中文翻译：

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尿路上皮：液体环境中的生命。


尿路上皮排列在肾盂、输尿管、膀胱和近端尿道上，形成一个高阻力但适应性强的屏障，监视其机械化学环境并将变化传达给包括传入神经纤维和平滑肌在内的底层组织。本综述的目的是总结过去十年中对尿路上皮生物学和功能的新见解。在让读者熟悉尿路上皮组织学的关键方面后，我们描述了对尿路上皮发育和再生的新见解。接下来是对尿路上皮屏障功能的扩展讨论，包括有关糖萼、离子和水运输、紧密连接以及细胞和组织形状变化以及伴随下尿路扩张和收缩的其他适应的作用的信息。我们还探索了尿路上皮可以在正常生理过程中和对过度扩张做出反应时改变尿液的水和溶质成分的证据。我们通过概述当前关于尿路上皮环境的知识，讨论尿路上皮的传感器和换能器功能，探索昼夜节律在尿路上皮基因表达中的作用，并描述可能进一步推进我们的新研究工具来完成综述。了解尿路上皮生物学。