Developing bronchopulmonary epithelium of the human fetus secretes fluid.
Developing bronchopulmonary epithelium of the human fetus secretes fluid.
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人类胎儿发育中的支气管肺上皮会分泌液体。
DOI：
10.1152/ajplung.1992.262.3.l270
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Bastacky,J
中科院分区：
文献类型：
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作者：
McCrayJr,PB;Bettencourt,JD;Bastacky,J
我们在浸泡器官培养中研究了人胎肺组织，以确定支气管肺上皮在发育过程中是否分泌液体。在这个系统中，腺泡小管继续生长，分泌液体，并逐渐扩张。在培养3-8天后，用微电极测量基线跨上皮电位差(Psit)为-0.5~-11 mV(平均-3.8 mV，管腔阴性，n=27)，表明电解质转运活跃。布美他尼(500微米)可使基础psi从-5+/-1.5降至-3.2+/-1.6(SE)mV(P<0.05，n=6)，提示氯离子转运对电压有贡献。异丙肾上腺素(5微米)使基础psi由-5.6+/-2.1升至-9.2+/-2.5(SE)mV(P<0.05，n=4)。随后加入布美他尼可使异丙肾上腺素引起的PSI抑制20%(P<0.05)。8-(4-氯苯硫基)腺苷3‘，5’-环一磷酸。CPT-cAMP(50微米)和3-异丁基-1-甲基黄嘌呤(IBMX，100微米)有相似的作用，使Psit从-2.2+/-0.5增加到-8+/-1.6(SE)mV，这种作用可被布美他尼(P<0.005，n=6)所抑制。与对照组相比，异丙肾上腺素和CPT-cAMP/IBMX处理后12 h和24 h外植体的管腔面积百分比均显著增加。我们的结论是：1)发育中的支气管肺上皮(腺泡小管)有助于人胎儿肺液的产生；2)胎儿肺液的分泌是氯离子依赖的；3)β-激动剂和cAMP可能刺激了肺液的分泌。
We studied human fetal lung tissue in submersion organ culture to determine whether the bronchopulmonary epithelium secretes fluid during development. In this system the acinar tubules continued to grow, secrete fluid, and become progressively dilated. Baseline transepithelial potential differences (psi t) of -0.5 to -11 mV (mean, -3.8 mV, lumen negative, n = 27) were measured with microelectrodes after 3-8 days in culture, suggesting active electrolyte transport. Bumetanide (500 microM), an inhibitor of chloride secretion in other systems, decreased the basal psi t from -5 +/- 1.5 to -3.2 +/- 1.6 (SE) mV (P less than 0.05, n = 6), suggesting that chloride transport contributed to the voltage. Isoproterenol (5 microM) increased the baseline psi t from -5.6 +/- 2.1 to -9.2 +/- 2.5 (SE) mV (P less than 0.05, n = 4). Subsequent addition of bumetanide inhibited the isoproterenol-induced stimulation of the psi t by 20% (P less than 0.05). 8-(4-chlorophenylthio)adenosine 3',5'-cyclic monophosphate. (CPT-cAMP, 50 microM) and 3-isobutyl 1-methylxanthine (IBMX, 100 microM) had similar effects, causing an increase in the psi t from -2.2 +/- 0.5 to -8 +/- 1.6 (SE) mV, an effect that was inhibited by the addition of bumetanide (P less than 0.005, n = 6). Both isoproterenol and CPT-cAMP/IBMX produced significant increases in the percentage luminal area of the explants at 12 and 24 h after exposure compared with control. We conclude that 1) the developing bronchopulmonary epithelium (acinar tubules) contributes to lung fluid production in the human fetus, 2) fetal lung fluid secretion is chloride dependent, and 3) chloride secretion and fluid secretion may be stimulated by a beta-agonist and cAMP.