Chiang M, Robinson K R, Vanable J W
Department of Biological Sciences, Purdue University, West Lafayette, IN 47907.
Exp Eye Res. 1992 Jun;54(6):999-1003. doi: 10.1016/0014-4835(92)90164-n.
A lateral potential drop along the outer surface of the cornea could be measured at the edge of wounds made in the corneal epithelium of the isolated bovine eye when the cornea was covered by simulated tear film of modified Hanks' solution. These lateral fields (LFs) had an average magnitude of 42 +/- 1.4 mV mm-1 in the first 0.25 mm from the wound edge. The polarity of these surface LFs is more positive at the wound than in regions away from the wound. Very little if any lateral field could be measured at the edge of wounds along the inner surface of the corneal epithelium. The surface LFs depend on the cornea's transepithelial potential (TEP), which in this isolated bovine eye preparation we determined (with conventional microelectrode techniques) to have an average value of 24.7 +/- 2.2 mV, stroma-side positive. We found that this TEP drives a current from wounds in the epithelium with an average current density of 55 +/- 12 microA cm-2. We also have found that the average transcorneal potential (TCP) was 3.2 +/- 0.5 mV greater than the average TEP, confirming that the major contribution to the TCP comes from the corneal epithelium.
当角膜被改良的汉克斯溶液模拟泪膜覆盖时，在离体牛眼角膜上皮伤口边缘可测量到沿角膜外表面的横向电位降。在距伤口边缘最初的0.25毫米内，这些横向电场（LFs）的平均大小为42±1.4毫伏/毫米。这些表面LFs在伤口处的极性比远离伤口的区域更正。沿角膜上皮内表面伤口边缘几乎测不到横向电场。表面LFs取决于角膜的跨上皮电位（TEP），在这种离体牛眼标本中，我们（用传统微电极技术）测定其平均值为24.7±2.2毫伏，基质侧为正。我们发现，这种TEP驱动来自上皮伤口的电流，平均电流密度为55±12微安/平方厘米。我们还发现，平均跨角膜电位（TCP）比平均TEP大3.2±0.5毫伏，这证实了对TCP的主要贡献来自角膜上皮。
