O'Riordan D K, Sharp P, Sykes R M, Srai S K, Epstein O, Debnam E S
Department of Medicine, Royal Free Hospital School of Medicine, London, UK.
Eur J Clin Invest. 1995 Oct;25(10):722-7. doi: 10.1111/j.1365-2362.1995.tb01950.x.
Haemolytic anaemia induced by phenylhydrazine (PZ) promotes iron absorption across rat small intestine. This present study investigates the role of the brush border potential difference (Vm) and mucosal reducing activity in the response. In addition, quantitative autoradiography was used to assess PZ-induced changes in the villus localization of brush border iron uptake. Iron transfer from duodenum to blood was increased significantly 5 days after treatment with PZ. Autoradiography showed that most brush border iron uptake occurred at the upper villus region and the maximal rate was increased fourfold by PZ. Duodenal villus length was increased in PZ-treated rats. PZ treatment did not influence mucosal reducing activity but Vm, measured using duodenal sheets, increased from -50 to -57 mV (P < 0.001) and this was due to a reduced brush border sodium permeability. Thus, an expanded absorptive surface and an enhanced electrical driving force for iron uptake across the duodenal brush border are important adaptations for increased iron absorption in PZ-induced haemolytic anaemia.
苯肼（PZ）诱导的溶血性贫血促进铁在大鼠小肠中的吸收。本研究调查了刷状缘电位差（Vm）和黏膜还原活性在该反应中的作用。此外，定量放射自显影术用于评估PZ诱导的刷状缘铁摄取绒毛定位变化。用PZ治疗5天后，十二指肠到血液的铁转运显著增加。放射自显影显示，大多数刷状缘铁摄取发生在绒毛上部区域，最大摄取率因PZ而增加了四倍。PZ处理的大鼠十二指肠绒毛长度增加。PZ处理不影响黏膜还原活性，但使用十二指肠片测量的Vm从-50 mV增加到-57 mV（P < 0.001），这是由于刷状缘钠通透性降低所致。因此，扩大的吸收表面和增强的跨十二指肠刷状缘铁摄取电驱动力是PZ诱导的溶血性贫血中增加铁吸收的重要适应性变化。
