title: Phospholipase activities of surfactant fractions and their role in the morphological change in surfactants in vitro.
abstract: Rat lung surfactants including lamellar body, common myelin and tubular myelin were evaluated for enzyme activities of phospholipase A and phospholipase C using [14C] phosphatidylcholine as the substrate. The metabolic profiles of phosphatidylcholine were correlated with ultrastructural changes of each fraction in vitro incubation to elucidate whether any of these enzymes has a role in the morphological change. Lamellar body showed phospholipase A and phospholipase C activities at neutral pH. Electron microscopic observation showed that although these enzymes had no direct role in change of integration of the lamellar body to lattice tubule, phospholipase C had a role in modulation of the lamellar body to loose lamellae, and phospholipase A had a role in degradation of lattice integration.
authors.affiliation: Central Institute for Electron Microscopic Research, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kishikawa
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D000818:Animals; D002250:Carbon Radioisotopes; D002458:Cell Fractionation; D002479:Inclusion Bodies / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D008168:Lung / Q000166:cytology / Q000201:enzymology / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D009186:Myelin Sheath / Q000737:chemistry / Q000378:metabolism; D010618:Phenanthrolines / Q000494:pharmacology; D010713:Phosphatidylcholines / Q000032:analysis; D010740:Phospholipases / Q000378:metabolism* / Q000502:physiology; D011663:Pulmonary Surfactants / Q000032:analysis / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D000098:Acetophenones; D002250:Carbon Radioisotopes; D010618:Phenanthrolines; D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D010740:Phospholipases; C006821:4-bromophenacyl bromide