Characterization of alveolar epithelial cells type II during postnatal lung development in relation to alveolarization – Stereological studies of rat lungs
Fig 8
Various parameters characterizing Lb before, during and after bulk alveolarization (adulthood).
a) Volume density of Lb. In lungs of 21 days old rats significant higher values compared to 3 days and 7 days old rats were determined. b) Before and during alveolarization the surface density of Lb doesn´t change. A significant increase was found in adults compared to 3 and 7 days old rats. c) The total volume of Lb in AEII obtained by multiplying VV(Lb/AEII) with νN(AEII, lung) is comparable before and during bulk alveolarization. A significant increase was determined in AEII of adults. d) The total surface of Lb in AEII obtained by multiplying SV(Lb/AEII) with νN(AEII) doesn´t change until postnatal day 21. A significant increase compared to 3 and 7 days old lungs was found in adults. e) The total volume of Lb in the lung calculated by multiplying VV(Lb/AEII) with νN(AEII) and N(AEII, lung) over all age groups. Between 3 and 21 days old lungs a significant increase was found. Compared to 3 and 7 days old pups the significant highest values are seen in adults. f) The total surface of Lb in the lung calculated by multiplying SV(Lb/AEII) with νN(AEII) and N(AEII, lung) over all age groups. Between 3 and 21 days old lungs a significant increase was found.