Gorodeski G I, Hopfer U, Eckert R L, Utian W H, De Santis B J, Rorke E A, Romero M F
Department of Reproductive Biology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106.
Am J Physiol. 1994 Jun;266(6 Pt 1):C1692-8. doi: 10.1152/ajpcell.1994.266.6.C1692.
We studied the effect of ATP on transepithelial transport through the paracellular pathway in human cervical cells. Transepithelial conductance and transepithelial permeability (determined from the measurements of unidirectional flux of inert molecules) were measured in Caski cells grown on permeable support. Transepithelial conductance was 55.9 +/- 17.7 mS/cm2 and permeability was 12.5 +/- 2.7 x 10(-6) cm/s for a 0.51-kDa probe. Addition of ATP to the medium decreased acutely and reversibly the conductance and the permeability to probes between 0.18 and 10 kDa by 23-31% in a dose-related fashion; the 50% effective concentration was 1 microM, with a maximal effect at 5-10 microM extracellular ATP. The ATP effect was observed regardless of the pressure gradient across the epithelium. These results indicate that extracellular ATP in micromolar concentrations decreases acutely and reversibly the permeability through the paracellular pathway in cervical cells, possibly by affecting the permeability of the tight junctions and the resistance of the intercellular space. On the basis of these data, we speculate that ATP may play a role in the regulation of solutes and fluid transport across the cervical epithelium in vivo.
我们研究了ATP对人宫颈细胞经细胞旁途径进行跨上皮转运的影响。在生长于可渗透支持物上的Caski细胞中测量跨上皮电导和跨上皮通透性（通过惰性分子单向通量的测量来确定）。对于一种0.51 kDa的探针，跨上皮电导为55.9±17.7 mS/cm2，通透性为12.5±2.7×10(-6) cm/s。向培养基中添加ATP会以剂量相关的方式使0.18至10 kDa探针的电导和通透性急剧且可逆地降低23 - 31%；50%有效浓度为1 μM，在细胞外ATP浓度为5 - 10 μM时达到最大效应。无论上皮细胞两侧的压力梯度如何，均可观察到ATP的效应。这些结果表明，微摩尔浓度的细胞外ATP会急剧且可逆地降低宫颈细胞经细胞旁途径的通透性，这可能是通过影响紧密连接的通透性和细胞间隙的电阻来实现的。基于这些数据，我们推测ATP可能在体内溶质和液体跨宫颈上皮的转运调节中发挥作用。
