TY - JOUR
T1 - Macrophage and type II cell catabolism of SP-A and saturated phosphatidylcholine in mouse lungs
AU - Gurel, Okyanus
AU - Ikegami, Machiko
AU - Chroneos, Zissis C.
AU - Jobe, Alan H.
PY - 2001
Y1 - 2001
N2 - Type II cells and macrophages are the major cells involved in the alveolar clearance and catabolism of surfactant. We measured type II cell and macrophage contributions to the catabolism of saturated phosphatidyl-choline and surfactant protein A (SP-A) in mice. We used intratracheally administered SP-A labeled with residualizing 125I-dilactitol-tyramine, radiolabeled dipalmitoylphosphatidylcholine ([3H]DPPC), and its degradation-resistant analog [14C]DPPC-ether. At 15 min and 7, 19, 29, and 48 h after intratracheal injection, the mice were killed; alveolar lavage was then performed to recover macrophages and surfactant. Type II cells and macrophages not recovered by the lavage were subsequently isolated by enzymatic digestion of the lung. Radioactivity was measured in total lung, lavage fluid macrophages, alveolar washes, type II cells, and lung digest macrophages. Approximately equal amounts of 125I-dilactitol-tyramine-SP-A and [14C]DPPC-ether associated with the macrophages (lavage fluid plus lung digest) and type II cells when corrected for the efficiency of type II cell isolation. Eighty percent of the macrophage-associated radiolabel was recovered from lung digest macrophages. We conclude that macrophages and type II cells contribute equally to saturated phosphatidylcholine and SP-A catabolism in mice.
AB - Type II cells and macrophages are the major cells involved in the alveolar clearance and catabolism of surfactant. We measured type II cell and macrophage contributions to the catabolism of saturated phosphatidyl-choline and surfactant protein A (SP-A) in mice. We used intratracheally administered SP-A labeled with residualizing 125I-dilactitol-tyramine, radiolabeled dipalmitoylphosphatidylcholine ([3H]DPPC), and its degradation-resistant analog [14C]DPPC-ether. At 15 min and 7, 19, 29, and 48 h after intratracheal injection, the mice were killed; alveolar lavage was then performed to recover macrophages and surfactant. Type II cells and macrophages not recovered by the lavage were subsequently isolated by enzymatic digestion of the lung. Radioactivity was measured in total lung, lavage fluid macrophages, alveolar washes, type II cells, and lung digest macrophages. Approximately equal amounts of 125I-dilactitol-tyramine-SP-A and [14C]DPPC-ether associated with the macrophages (lavage fluid plus lung digest) and type II cells when corrected for the efficiency of type II cell isolation. Eighty percent of the macrophage-associated radiolabel was recovered from lung digest macrophages. We conclude that macrophages and type II cells contribute equally to saturated phosphatidylcholine and SP-A catabolism in mice.
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U2 - 10.1152/ajplung.2001.280.6.l1266
DO - 10.1152/ajplung.2001.280.6.l1266
M3 - Article
C2 - 11350807
AN - SCOPUS:0034983007
SN - 1040-0605
VL - 280
SP - L1266-L1272
JO - American Journal of Physiology - Lung Cellular and Molecular Physiology
JF - American Journal of Physiology - Lung Cellular and Molecular Physiology
IS - 6 24-6
ER -