The mammalian vascular system consists of two networks: the blood vascular system and the lymphatic vascular system. Throughout the body, the lymphatic system contributes to homeostatic mechanisms by draining extravasated interstitial fluid and facilitating the trafficking and activation of immune cells. In the kidney, lymphatic vessels exist mainly in the kidney cortex. In the medulla, the ascending vasa recta represent a hybrid lymphatic-like vessel that performs lymphatic-like roles in interstitial fluid reabsorption. Although the lymphatic network is mainly derived from the venous system, evidence supports the existence of lymphatic beds that are of non-venous origin. Following their development and maturation, lymphatic vessel density remains relatively stable; however, these vessels undergo dynamic functional changes to meet tissue demands. Additionally, new lymphatic growth, or lymphangiogenesis, can be induced by pathological conditions such as tissue injury, interstitial fluid overload, hyperglycaemia and inflammation. Lymphangiogenesis is also associated with conditions such as polycystic kidney disease, hypertension, ultrafiltration failure and transplant rejection. Although lymphangiogenesis has protective functions in clearing accumulated fluid and immune cells, the kidney lymphatics may also propagate an inflammatory feedback loop, exacerbating inflammation and fibrosis. Greater understanding of lymphatic biology, including the developmental origin and function of the lymphatics and their response to pathogenic stimuli, may aid the development of new therapeutic agents that target the lymphatic system.

哺乳动物的血管系统由两个网络组成：血管系统和淋巴血管系统。在整个身体中，淋巴系统通过排出外渗的间质液并促进免疫细胞的运输和激活来促进体内平衡机制。在肾脏中，淋巴管主要存在于肾皮质中。在髓质中，升直血管代表一种混合淋巴管，在间质液重吸收中发挥类似淋巴管的作用。尽管淋巴网络主要源自静脉系统，但有证据支持非静脉来源的淋巴床的存在。随着它们的发育和成熟，淋巴管密度保持相对稳定；然而，这些血管会经历动态的功能变化以满足组织需求。此外，组织损伤、间质液超负荷、高血糖和炎症等病理状况可以诱导新的淋巴管生长或淋巴管生成。淋巴管生成还与多囊肾病、高血压、超滤失败和移植排斥等疾病有关。尽管淋巴管生成在清除积聚的液体和免疫细胞方面具有保护性功能，但肾脏淋巴管也可能传播炎症反馈循环，加剧炎症和纤维化。更好地了解淋巴生物学，包括淋巴管的发育起源和功能及其对致病刺激的反应，可能有助于开发针对淋巴系统的新治疗药物。