In vitro system to study realistic pulsatile flow and stretch signaling in cultured vascular cells
In vitro system to study realistic pulsatile flow and stretch signaling in cultured vascular cells
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DOI：
10.1152/ajpcell.2000.279.3.c797
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发表时间：
2000-09-01
影响因子：
5.5
通讯作者：
Kass, DA
中科院分区：
文献类型：
--
作者：
Peng, XQ;Recchia, FA;Kass, DA
我们开发了一种新的实时伺服控制灌注系统，将生长在不可膨胀管或可膨胀管中的内皮细胞暴露在真实的脉冲压力和生理平均压力下的相位剪切下。流速控制泵和线性伺服电机由数字比例-积分-导数反馈控制，该反馈采用先前数字化的主动脉压力波作为命令信号。所得到的压力反映了记录的波形，并且可以通过数字修改来产生任何期望的平均和脉冲压力幅度，通常在0.5-15 dyn/cm(2)的剪切下为0-150 mmHg。该系统可以精确地再现所需的动脉压力波形，并通过压力与油管阻抗的相互作用产生生理流量和剪切。矩形玻璃毛细管[1毫米内径（ID）]用于实时荧光成像研究（即pH(i)， NO, Ca2+），而硅膨胀管（4毫米ID）用于更慢性（即2-24小时）关于信号转导和基因表达的研究。后者的弹性模量为12.4.10(6)dyn/cm(2)，类似于这种大小的体内血管，并使用台式系统进行研究。这种新方法首次在体外应用了血管细胞上真实的机械脉动力，并有助于研究相剪切和膨胀相互作用以及脉动信号转导。
We developed a novel realtime servo-controlled perfusion system that exposes endothelial cells grown in nondistensible or distensible tubes to realistic pulse pressures and phasic shears at physiological mean pressures. A rate-controlled flow pump and linear servo-motor are controlled by digital proportional-integral-derivative feedback that employs previously digitized aortic pressure waves as a command signal. The resulting pressure mirrors the recorded waveform and can be digitally modified to yield any desired mean and pulse pressure amplitude, typically 0-150 mmHg at shears of 0.5-15 dyn/cm(2). The system accurately reproduces the desired arterial pressure waveform and cogenerates physiological flow and shears by the interaction of pressure with the tubing impedance. Rectangular glass capillary tubes [1-mm inside diameter (ID)] are used for real-time fluorescent imaging studies (i.e., pH(i), NO, Ca2+), whereas silicon distensible tubes (4-mm ID) are used for more chronic (i.e., 2-24 h) studies regarding signal transduction and gene expression. The latter have an elastic modulus of 12.4.10(6) dyn/cm(2) similar to in vivo vessels of this size and are studied with the use of a benchtop system. The new approach provides the first in vitro application of realistic mechanical pulsatile forces on vascular cells and should facilitate studies of phasic shear and distension interaction and pulsatile signal transduction.