Lin Y, Lechner A J
Department of Physiology, St. Louis University School of Medicine, Missouri 63104.
Am J Physiol. 1990 Dec;259(6 Pt 1):L359-64. doi: 10.1152/ajplung.1990.259.6.L359.
Type II cells within guinea pig lungs were studied beginning when lamellar bodies (LB) were first identifiable, to determine the pattern of their ultrastructural maturation through parturition and to search for regional differences suggested for other species in their numbers or maturity within the same lung. Fetuses were examined at gestational ages of 55, 60, and 65 days, as were newborn within 2 h of birth at 68 days. The stratified sampling system divided left lungs into nine blocks from each cranial and caudal lobe for electron-microscopic morphometry. Type II cells were compared among blocks within lobes, between lobes within age groups, and among ages for volume densities [VV(ep2, t)], numerical densities [NV(ep2, t)], and surface densities [SV(ep2, t)] per block; total tissue volumes [V(ep2)], numbers [N(ep2)], and cumulative surface areas [S(ep2)] per lung; and the VV(lb, ep2) and V(lb) of their LB. Within lobes, there were no significant differences among blocks for any parameter. Within age groups, significant interlobar differences were limited only to NV(ep2, t) (cranial greater than caudal at day 55, P less than 0.001). In age-by-age comparisons, the V(ep2), NV(ep2), and S(ep2) each increased dramatically from day 55 to 60 (P less than 0.001) but then remained unchanged through parturition. However, both VV(lb, ep2) and V(lb) increased linearly with fetal age (day 55 less than 60 less than 65 less than newborn), with VV(lb, ep2) achieving 18% type II cell volume in the postpartum group.(ABSTRACT TRUNCATED AT 250 WORDS)
对豚鼠肺内的Ⅱ型细胞进行了研究，研究始于板层小体（LB）首次可识别之时，以确定其超微结构成熟模式直至分娩，并寻找其他物种所提示的同一肺内细胞数量或成熟度的区域差异。在妊娠55、60和65天时检查胎儿，在68天出生后2小时内检查新生儿。分层抽样系统将左肺从每个颅叶和尾叶分为九个块用于电子显微镜形态测量。比较各叶内不同块之间、年龄组内不同叶之间以及各年龄组之间Ⅱ型细胞的体积密度[VV(ep2, t)]、数量密度[NV(ep2, t)]和表面积密度[SV(ep2, t)]；每只肺的总组织体积[V(ep2)]、数量[N(ep2)]和累积表面积[S(ep2)]；以及其板层小体的VV(lb, ep2)和V(lb)。在叶内，任何参数在不同块之间均无显著差异。在年龄组内，显著的叶间差异仅局限于NV(ep2, t)（55天时颅叶大于尾叶，P<0.001）。在逐年龄比较中，V(ep2)、NV(ep2)和S(ep2)从55天到60天均显著增加（P<0.001），但随后直至分娩保持不变。然而，VV(lb, ep2)和V(lb)均随胎龄线性增加（55天<60天<65天<新生儿），产后组中VV(lb, ep2)达到Ⅱ型细胞体积的18%。（摘要截断于250字）
