Kawahara H, Wang X E, Takase S, Matsuda Y, Takada A
Department of Internal Medicine, Kanazawa Medical University, Ishikawa, Japan.
Alcohol Alcohol Suppl. 1993;1B:9-14. doi: 10.1093/alcalc/28.supplement_1b.9.
The effects of ethanol (Et-OH) and acetaldehyde (Ac-CHO) on the contraction of cultured Ito cells were studied using a time-interval videotape recorder (VTR). Ito cells were isolated from Wistar rats and cultured for 4 days. The motion of the cells was recorded by VTR and the sequential changes of the surface area of the each cell were evaluated by an image analyzer. No contraction of Ito cells was observed after incubation with Et-OH (100 mM) or Ac-CHO (500 microM) alone. Ten nanomoles endothelin-1 (ET-1) caused Ito cells to contract gradually. Pre-incubation of ET-1 with Ac-CHO at 37 degrees C for 1 hr inhibited the contraction of Ito cells completely. This inhibition was not seen in pre-incubation of ET-1 with Et-OH. In addition, the Ito cells which were pre-cultured with Ac-CHO for 6 hr did not contract at all after incubation with ET-1. In the isoelectric focusing of ET-1, a band was clearly seen at pI 4.6 after the treatment with Et-OH as well as non-treated ET-1. Two extra bands of ET-1 appeared in the anodic side of the gel after treatment with Ac-CHO, indicating the conformational changes of ET-1. These results indicated that the contraction of Ito cells induced by ET-1 was inhibited completely by Ac-CHO. This inhibitory effect of Ac-CHO was thought to be caused by binding Ac-CHO to ET-1 itself or to ET-1 receptors.
使用时间间隔录像机（VTR）研究了乙醇（Et-OH）和乙醛（Ac-CHO）对培养的肝星状细胞收缩的影响。从Wistar大鼠中分离出肝星状细胞并培养4天。通过VTR记录细胞的运动，并使用图像分析仪评估每个细胞表面积的连续变化。单独用Et-OH（100 mM）或Ac-CHO（500 microM）孵育后，未观察到肝星状细胞收缩。10纳摩尔的内皮素-1（ET-1）使肝星状细胞逐渐收缩。ET-1与Ac-CHO在37℃预孵育1小时可完全抑制肝星状细胞的收缩。ET-1与Et-OH预孵育时未观察到这种抑制作用。此外，预先用Ac-CHO培养6小时的肝星状细胞在与ET-1孵育后根本不收缩。在ET-1的等电聚焦中，用Et-OH处理后以及未处理的ET-1在pI 4.6处均可见一条清晰的条带。用Ac-CHO处理后，凝胶阳极侧出现两条额外的ET-1条带，表明ET-1发生了构象变化。这些结果表明，Ac-CHO可完全抑制ET-1诱导的肝星状细胞收缩。Ac-CHO的这种抑制作用被认为是由于Ac-CHO与ET-1本身或ET-1受体结合所致。
