CARTILAGE ELECTROMECHANICS .1. ELECTROKINETIC TRANSDUCTION AND THE EFFECTS OF ELECTROLYTE PH AND IONIC-STRENGTH
CARTILAGE ELECTROMECHANICS .1. ELECTROKINETIC TRANSDUCTION AND THE EFFECTS OF ELECTROLYTE PH AND IONIC-STRENGTH
复制标题
DOI：
10.1016/0021-9290(87)90282-x
复制
发表时间：
1987-01-01
影响因子：
2.4
通讯作者：
GRODZINSKY, AJ
中科院分区：
文献类型：
--
作者：
FRANK, EH;GRODZINSKY, AJ
关节软骨在生理条件下含有高固定电荷密度，主要与细胞外基质的电离蛋白聚糖分子相关。使用生理负荷对软骨进行振荡压缩会产生电势，先前已证明该电势是动电（流）传导机制的结果。我们现在观察到了软骨或其他软组织中以前未见过的两种额外机电现象：“流动电流”和“电流产生的应力”。当用于压缩软骨的 Ag/AgCl 电极在外部短接在一起时，正弦机械压缩会通过软骨盘感应出正弦流电流密度。相反，施加到组织的正弦电流密度在组织内产生正弦机械应力。发现这两种现象与负责流动电势的相同动电转导机制一致。由于离子强度和 pH 值的改变而导致测量到的流动电位响应发生变化，这为了解这些转导过程的分子起源提供了额外的见解。最后，我们现在观察到了器官培养中维持的活软骨以及先前冷冻的组织中的流动电位。
Articular cartilage contains a high fixed charge density under physiological conditons associated primarily with the ionized proteoglycan molecules of the extracellular matrix. Oscillatory compression of cartilage using physiological loads produces electrical potentials that have been shown previously to be the result of an electrokinetic (streaming) transduction mechanism. We have now observed two additional electromechanical phenomena not previously seen in cartilage or other soft tissues: ''streaming current'' and ''current-generated stress''. Sinusoidal mechanical compression induced a sinusoidal streaming current density through cartilage disks when the Ag/AgCl electrodes that were used to compress the cartilage were shorted together externally. Conversely, a sinusoidal current density applied to the tissue generated a sinusoidal mechanical stress within the tissue. Both these phenomena were found to be consistent with the same electrokinetic transduction mechanism responsible for the streaming potential. Changes in the measured streaming potential response that resulted from modification of both ionic strength and pH have provided additional insights into the molecular origins of these transduction processes. Finally, we have now observed streaming potentials in living cartilage maintained in organ culture, as well as in previously frozen tissue.