Swartz M A, Berk D A, Jain R K
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge 02139, USA.
Am J Physiol. 1996 Jan;270(1 Pt 2):H324-9. doi: 10.1152/ajpheart.1996.270.1.H324.
We present a novel integrative method for characterizing transport in the lymphatic capillaries in the tail of the anesthetized mouse, which is both sensitive and reproducible for quantifying uptake and flow. Interstitially injected, fluorescently labeled macromolecules were used to visualize and quantify these processes. Residence time distribution (RTD) theory was employed to measure net flow velocity in the lymphatic network as well as to provide a relative measure of lymphatic uptake of macromolecules from the interstitium. The effects of particle size and injection pressure were determined. The uptake rate was found to be independent of particle size in the range of a 6- to 18-nm radius; beyond this size, the interstitial matrix seemed to pose a greater barrier. A comparison of 10 vs. 40 cmH2O injection pressure showed a significant influence on the relative uptake rate but not on the net velocity within the network (3.3 +/- 0.8 vs. 3.8 +/- 1.0 micron/s). This suggested the presence of a systemic driving force for baseline lymph propulsion that is independent of the local pressure gradients driving the uptake. This model can be used to examine various aspects of transport physiology of the initial lymphatics.
我们提出了一种新颖的综合方法，用于表征麻醉小鼠尾巴淋巴管中的物质运输，该方法在量化摄取和流动方面既灵敏又可重复。通过间质注射荧光标记的大分子来可视化和量化这些过程。采用停留时间分布（RTD）理论来测量淋巴网络中的净流速，并提供大分子从间质中淋巴摄取的相对测量值。确定了颗粒大小和注射压力的影响。发现在半径6至18纳米范围内摄取速率与颗粒大小无关；超过这个尺寸，间质基质似乎构成了更大的屏障。10厘米水柱与40厘米水柱注射压力的比较表明，对相对摄取速率有显著影响，但对网络内的净流速没有影响（3.3±0.8对3.8±1.0微米/秒）。这表明存在一种用于基线淋巴推进的全身驱动力，其独立于驱动摄取的局部压力梯度。该模型可用于研究初始淋巴管运输生理学的各个方面。
