C. Romero et al., EFFECT OF ESCHERICHIA-COLI LIPOPOLYSACCHARIDE ON SURFACTANT SECRETIONIN PRIMARY CULTURES OF RAT TYPE-II PNEUMOCYTES, Biochimica et biophysica acta, L. Lipids and lipid metabolism, 1256(3), 1995, pp. 305-309
The purpose of this study is to evaluate the effect of the Escherichia
coli lipopolysaccharide on the secretion of phosphatidylcholine, the
principal component of pulmonary surfactant, in primary cultures of ra
t alveolar type II pneumocytes. Lipopolysaccharide stimulated phosphat
idylcholine secretion in a time- and dose-dependent manner. At a conce
ntration of 200 mu g/ml, lipopolysaccharide stimulated the release of
phosphatidylcholine 4-fold over the basal secretory rate, and the conc
entration producing half the maximal response was 20 mu g/ml. The stim
ulatory effect of lipopolysaccharide on phosphatidylcholine secretion
was additive to that of the protein kinase C activator TPA, which is a
potent stimulator of surfactant secretion. Lipopolysaccharide did not
activate protein kinase C, which suggests that stimulation of phospha
tidylcholine secretion by the endotoxin was through a mechanism indepe
ndent of protein kinase C activation.