一方面,淋巴功能障碍引起间质水肿和炎症。另一方面,水肿和炎症的形成引起淋巴功能障碍。然而,由早期报道的辐射的淋巴内皮细胞(LEC)体内未检测到的凋亡,淋巴管通常被认为与电离辐射(IR)诱导的正常组织的炎症损伤无关。主要是因为对IR暴露对淋巴功能的急性影响缺乏了解,急性水肿和炎症,红外暴露的常见后遗症,完全是因为血管损伤.因此,在本研究中,对IR暴露的淋巴管急性反应进行了量化,以评估IR暴露损害淋巴管泵的假设.在体内或体外照射大鼠肠系膜淋巴管,并在体外对分离的血管中的泵送变化进行定量。与假处理的血管相比,在体内辐照的淋巴管中,泵送降低,但在体外辐照的血管中泵送增加。此外,与血管不同,在体内或体外照射的血管中,淋巴管中IR暴露的急性效应均不受一氧化氮依赖性途径的介导。环氧合酶阻断后,在体外照射的淋巴管中部分恢复了泵送,但在体内照射的血管中没有恢复。一起来看,这些发现表明,淋巴管对放射敏感,单独的LEC细胞凋亡可能不能解释IR暴露对淋巴系统的所有影响.NEW&NOTEWORTHY早期的研究导致人们普遍认为淋巴管是耐放射性的,或者没有表征淋巴泵,认为是解决水肿和炎症所必需的,或者是在体内做的。通过表征体外泵送,本研究,第一次,证明了在体内辐照的血管中淋巴泵送受损,而在体外辐照的血管中淋巴泵送增强。此外,与电离辐射诱导的血管损伤有关的通路并不介导淋巴反应.
On the one hand, lymphatic dysfunction induces interstitial edema and inflammation. On the other hand, the formation of edema and inflammation induce lymphatic dysfunction. However, informed by the earlier reports of undetected apoptosis of irradiated lymphatic endothelial cells (LECs) in vivo, lymphatic vessels are commonly considered inconsequential to ionizing radiation (IR)-induced inflammatory injury to normal tissues. Primarily because of the lack of understanding of the acute effects of IR exposure on lymphatic function, acute edema and inflammation, common sequelae of IR exposure, have been ascribed solely to blood vessel damage. Therefore, in the present study, the lymphatic acute responses to IR exposure were quantified to evaluate the hypothesis that IR exposure impairs lymphatic pumping. Rat mesenteric lymphatic vessels were irradiated in vivo or in vitro, and changes in pumping were quantified in isolated vessels in vitro. Compared with sham-treated vessels, pumping was lowered in lymphatic vessels irradiated in vivo but increased in vessels irradiated in vitro. Furthermore, unlike in blood vessels, the acute effects of IR exposure in lymphatic vessels were not mediated by nitric oxide-dependent pathways in either in vivo or in vitro irradiated vessels. After cyclooxygenase blockade, pumping was partially restored in lymphatic vessels irradiated in vitro but not in vessels irradiated in vivo. Taken together, these findings demonstrated that lymphatic vessels are radiosensitive and LEC apoptosis alone may not account for all the effects of IR exposure on the lymphatic system.NEW & NOTEWORTHY Earlier studies leading to the common belief that lymphatic vessels are radioresistant either did not characterize lymphatic pumping, deemed necessary for the resolution of edema and inflammation, or did it in vivo. By characterizing pumping in vitro, the present study, for the first time, demonstrated that lymphatic pumping was impaired in vessels irradiated in vivo and enhanced in vessels irradiated in vitro. Furthermore, the pathways implicated in ionizing radiation-induced blood vessel damage did not mediate lymphatic responses.