Amino acid and sugar transport in rabbit ileum.
Amino acid and sugar transport in rabbit ileum.
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DOI：
10.1085/jgp.49.5.849
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发表时间：
1966-05
期刊：
影响因子：
--
通讯作者：
Curran PF
中科院分区：
文献类型：
--
作者：
Schultz SG;Fuisz RE;Curran PF
研究了兔回肠粘膜条对l-丙氨酸和3- o -甲基- d -葡萄糖的积累，特别强调了Na与这些运输过程之间的相互作用。l -丙氨酸通过粘膜组织迅速积累，当细胞外l -丙氨酸浓度为5 mM时，细胞内浓度在30分钟内达到约50 mM。有证据表明，细胞内丙氨酸以非结合的渗透活性形式存在，积累是一个主动的运输过程。在缺乏细胞外钠的情况下，细胞内和细胞外l -丙氨酸的最终比例与统一时没有显著差异，净吸收率明显受到抑制。氨基酸的积累也被5 × 10-5 M瓦苦因所抑制。该制剂的3- o -甲基- d -葡萄糖积累同样受到乌阿班和在无na培养基中培养的影响。氨基酸积累、瓦巴因和在无Na培养基中培养对细胞含水量和细胞内Na和K浓度的影响也进行了研究。这些结果与已经提出的解释钠与肠道非电解质转运之间相互作用的两种假设进行了讨论。
L-Alanine and 3-O-methyl-D-glucose accumulation by mucosal strips from rabbit ileum has been investigated with particular emphasis on the interaction between Na and these transport processes. L-Alanine is rapidly accumulated by mucosal tissue and intracellular concentrations of approximately 50 mM are reached within 30 min when extracellular L-alanine concentration is 5 mM. Evidence is presented that intracellular alanine exists in an unbound, osmotically active form and that accumulation is an active transport process. In the absence of extracellular Na, the final ratio of intracellular to extracellular L-alanine does not differ significantly from unity and the rate of net uptake is markedly inhibited. Amino acid accumulation is also inhibited by 5 x 10-5 M ouabain. 3-O-methyl-D-glucose accumulation by this preparation is similarly affected by ouabain and by incubation in a Na-free medium. The effects of amino acid accumulation, of ouabain, and of incubation in a Na-free medium on cell water content and intracellular Na and K concentrations have also been investigated. These results are discussed with reference to the two hypotheses which have been suggested to explain the interaction between Na and intestinal nonelectrolyte transport.