Inhibition of surfactant release from isolated Type II cells by compound 48/80.
Release of [3H]phosphatidylcholine from pulmonary Type II epithelial cells was stimulated by terbutaline, forskolin and cytochalasin D. Compound 48/80 inhibited both basal and agonist-stimulated release of [3H]PC. The IC50 for inhibition by compound 48/80 was 1-2 micrograms/ml, and was similar for inhibition of both basal and stimulated release of [3H]phosphatidylcholine. Inhibitory effects of 48/80 were noted following a 1 h exposure to compound 48/80 and persisted up to 3 h. The inhibitory effect of compound 48/80 was entirely reversed by removing compound 48/80 from the external milieu. Compound 48/80 had no effect on cytosolic cyclic AMP levels or lactate dehydrogenase release. Inhibition of surfactant release produced by compound 48/80 was unaffected by changes in extracellular calcium concentrations. Compound 48/80 is a non-toxic inhibitor of phosphatidylcholine release from Type II epithelial cells.
D000818:Animals; D002478:Cells, Cultured; D005576:Colforsin; D003572:Cytochalasins / Q000494:pharmacology; D004224:Diterpenes / Q000494:pharmacology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D011650:Pulmonary Alveoli / Q000378:metabolism*; D011663:Pulmonary Surfactants / Q000378:metabolism*; D051381:Rats; D012636:Secretory Rate / Q000187:drug effects; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology*
D003572:Cytochalasins; D004224:Diterpenes; D011663:Pulmonary Surfactants; D005576:Colforsin; D003189:p-Methoxy-N-methylphenethylamine; D007770:L-Lactate Dehydrogenase