title: Effect of atrial natriuretic factor on the water permeability of endothelial cells.
abstract: Atrial natriuretic factor increases the water permeability of the whole endothelium. This study investigates how it would affect the transcellular osmotic water permeability of bovine artery endothelial cells. The cyclic-GMP production by the isolated cells was maximal for 10(-6)M atrial natriuretic factor within 30 minutes at 37 degrees C. The cyclic-GMP protein kinase cell concentration was 1.87 +/- 0.15 ng/mg protein. The control apparent water permeability of the cells measured by light scattering was 195 +/- 11 microns/sec (n = 5). Membrane folding revealed by light and scanning electron microscopy indicated that their true water permeability values would be close to 20-40 microns/sec, similar to the values for lipid membranes. The energy activation calculated from the temperature dependence of water permeability between 15 degrees C and 37 degrees C was 9.3 kcal/mol. This value suggests water movement through the lipid bilayer and not through water channels. Atrial natriuretic factor 10(-6)M did not significantly increase the water permeability of the cells. Hence, atrial natriuretic factor-stimulated increase in water permeability of the endothelium is more related to changes in paracellular water pathways than in transcellular water flux.
authors.affiliation: INSERM unité 367, Paris, France.
authors.forename: T
authors.initials: T
authors.lastname: Battle
authors.forename: J B
authors.initials: JB
authors.lastname: Michel
authors.forename: B
authors.initials: B
authors.lastname: Corman
mesh_terms: D000818:Animals; D001158:Arteries / Q000378:metabolism; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002417:Cattle; D002463:Cell Membrane Permeability / Q000187:drug effects*; D006152:Cyclic GMP / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism*; D006358:Hot Temperature; D014867:Water / Q000378:metabolism*
chemical_list: D014867:Water; D009320:Atrial Natriuretic Factor; D006152:Cyclic GMP