Fox J E, Morris G P, Beck I T, McElligott T F
Can J Physiol Pharmacol. 1979 Mar;57(3):305-13. doi: 10.1139/y79-046.
Previous light microscopic studies showed that perfusion of the hamster jejunum with 4.8% ethanol (ethanol period) in vivo produced fluid-filled subepithelial blisters (blebs) on the villi. These blebs had virtually disappeared within 45 min after the discontinuation of the ethanol perfusion (recovery period). The present study examined these ethanol-induced changes in the jejunum by scanning (SEM) and transmission (TEM) electron microscopy. TEM revealed that ethanol did not damage epithelial cells in areas where blebs were not present. In these areas the basal surfaces of the epithelial cells were attached to the basal lamina, and the lateral intercellular spaces (LIS) were open. In the areas where blebs formed, the stretched epithelial cells which covered the blebs lost their basal anchoring and so could not maintain their LIS. Both SEM and TEM indicate that there was a decrease in the quantity of glycocalyx at the surfaces of cells which covered blebs. Our findings indicate that ethanol does not directly damage epithelial cells but that the cellular damage is due to detachment over the blebs. It is likely that ethanol at first traverses the epithelial layer and then produces stasis in the villus core. Continued fluid transport by the epithelial layer in the presence of statis results in accumulation of the fluid and widely dilated LIS. With subsequent enlargement of the LIS the bases of the cells detach from the basal lamina and blebs are formed.
以往的光学显微镜研究表明，在体内用4.8%乙醇灌注仓鼠空肠（乙醇灌注期）会在绒毛上产生充满液体的上皮下水泡（泡）。在停止乙醇灌注后45分钟内（恢复期），这些水泡几乎消失。本研究通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）检查了乙醇诱导的空肠变化。TEM显示，在没有水泡的区域，乙醇不会损伤上皮细胞。在这些区域，上皮细胞的基底表面附着于基膜，侧向细胞间隙（LIS）开放。在形成水泡的区域，覆盖水泡的拉伸上皮细胞失去了基底锚定，因此无法维持其LIS。SEM和TEM均表明，覆盖水泡的细胞表面糖萼数量减少。我们的研究结果表明，乙醇不会直接损伤上皮细胞，而是细胞损伤是由于水泡上方的脱离。乙醇可能首先穿过上皮层，然后在绒毛核心产生淤滞。在存在淤滞的情况下，上皮层持续进行液体运输会导致液体积聚和LIS广泛扩张。随着LIS随后扩大，细胞基部与基膜分离并形成水泡。
