Smith C I, Hilfer S R, Searls R L, Nathanson M A, Allodoli M D
Department of Biology, Temple University, Philadelphia, Pennsylvania 19122.
Dev Biol. 1990 Mar;138(1):42-52. doi: 10.1016/0012-1606(90)90175-i.
Differentiation of respiratory endings in the fetal lung appears to be controlled by its surrounding mesodermal capsule. The capsule may exert its influence by controlling the composition of the epithelial basal lamina or of the extended extracellular matrix that is deposited during the period when alveolar sacs are formed. As a first step in testing this hypothesis, the effects of the drug, rho-nitrophenyl-beta-D- xylopyranoside (beta-xyloside), an inhibitor of proteoglycan synthesis, and its inactive alpha anomer (alpha-xyloside) were examined. Lung primordia from mice at 16 days of gestation were tested for inhibition of morphological and functional differentiation as a result of drug treatment. Pseudoglandular lung epithelium did not form respiratory endings, contained fewer specialized cells, and accumulated little additional surfactant when treated with beta-xyloside but developed normally when treated with alpha-xyloside or grown in control medium. The results are interpreted to suggest that deposition of an extracellular matrix rich in proteoglycan is required to support maturation of the respiratory epithelium.
胎儿肺中呼吸终末的分化似乎受其周围中胚层被膜的控制。该被膜可能通过控制上皮基膜或在肺泡囊形成期间沉积的扩展细胞外基质的组成来发挥其影响。作为检验这一假设的第一步，研究了药物ρ-硝基苯基-β-D-吡喃木糖苷（β-木糖苷）（一种蛋白聚糖合成抑制剂）及其无活性的α异头物（α-木糖苷）的作用。对妊娠16天小鼠的肺原基进行检测，以观察药物处理对形态和功能分化的抑制作用。用β-木糖苷处理时，假腺泡肺上皮未形成呼吸终末，含有较少的特化细胞，且几乎没有积累额外的表面活性剂，但用α-木糖苷处理或在对照培养基中生长时则正常发育。这些结果被解释为表明需要富含蛋白聚糖的细胞外基质的沉积来支持呼吸上皮的成熟。
