Benedetti A, Tangorra A, Svegliati Baroni G, Ferretti G, Marucci L, Jezequel M, Orlandi F
Department of Gastroenterology, University of Ancona, Italy.
Am J Physiol. 1994 Feb;266(2 Pt 1):G282-91. doi: 10.1152/ajpgi.1994.266.2.G282.
Hepatic ethanol (EtOH) metabolism has been assumed to involve hepatocytes differently, according to their location in the hepatic acinus. This study's aim was to gain information on plasma membrane (PM) order parameter in periportal (PP) and perivenular (PV) hepatocyte-enriched fractions isolated by a digitonin-collagenase perfusion technique from rats pair-fed for 6-8 wk liquid diets containing either EtOH or isocaloric carbohydrates. Fluorescence polarization (P) studies have been performed to measure PM order parameter of PP and PV hepatocytes cultured for 2-6 h on glass cover slips and labeled with 1-[4-(trimethylamino)phenyl]-6-phenylhexa-1,3,5-triene (TMA-DPH), a specific probe for PM of living cells. Fluorescence polarization and microscopy indicated that TMA-DPH is a suitable probe to study PM order parameter in subconfluent rat hepatocyte monolayers where it labeled, after a rapid incorporation, PM of cells. In pair-fed control rats, PM order parameter was lower in PP hepatocytes than in PV cells (P = 0.366 +/- 0.013 vs. 0.381 +/- 0.021, respectively, P < 0.02; n = 7). In EtOH-treated rats, these zonal differences tended to disappear (P = 0.419 +/- 0.012 in PP cells vs. 0.417 +/- 0.007 in PV cells; n = 7). In addition, the order parameter was significantly higher either in PP or PV hepatocytes compared with pair-fed control animals (P < 0.002 and 0.003, respectively). A 30-min culture of cells in the presence of 40-200 mM EtOH significantly decreased the PM order parameter of hepatocytes isolated from pair-fed control rats with respect to EtOH-treated animals both in PP and PV cells (P < 0.01 and 0.02, respectively; n = 4).(ABSTRACT TRUNCATED AT 250 WORDS)
肝乙醇（EtOH）代谢被认为根据肝腺泡中肝细胞的位置不同而涉及不同的肝细胞。本研究的目的是获取有关通过洋地黄皂苷 - 胶原酶灌注技术从成对喂养6 - 8周含EtOH或等热量碳水化合物的液体饮食的大鼠中分离出的门静脉周围（PP）和肝静脉周围（PV）富含肝细胞的部分中质膜（PM）有序参数的信息。进行了荧光偏振（P）研究，以测量在玻璃盖玻片上培养2 - 6小时并用1 - [4 - （三甲氨基）苯基] - 6 - 苯基己 - 1,3,5 - 三烯（TMA - DPH）标记的PP和PV肝细胞的PM有序参数，TMA - DPH是活细胞PM的特异性探针。荧光偏振和显微镜检查表明，TMA - DPH是研究亚汇合大鼠肝细胞单层中PM有序参数的合适探针，在快速掺入后，它标记了细胞的PM。在成对喂养的对照大鼠中，PP肝细胞中的PM有序参数低于PV细胞（分别为P = 0.366±0.013对0.381±0.021，P <0.02；n = 7）。在乙醇处理的大鼠中，这些区域差异趋于消失（PP细胞中P = 0.419±0.012，PV细胞中P = 0.417±0.007；n = 7）。此外，与成对喂养的对照动物相比，PP或PV肝细胞中的有序参数均显著更高（分别为P <0.002和0.003）。在40 - 200 mM EtOH存在下对细胞进行30分钟培养，与乙醇处理的动物相比，从成对喂养的对照大鼠分离的肝细胞在PP和PV细胞中的PM有序参数均显著降低（分别为P <0.01和0.02；n = 4）。（摘要截断于250字）
