title: A study of the perturbation effects of the local anesthetic procaine on human erythrocyte and model membranes and of modifications of the sodium transport in toad skin.
abstract: The interaction of the local anesthetic procaine with human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), isolated toad skins, and molecular models is described. The latter consisted of phospholipid multilayers built-up of dimyristoylphosphatidylcholine (DMPC) and of dimyristoylphosphatidylethanolamine (DMPE), representatives of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. Optical and scanning electron microscopy of human erythrocytes revealed that procaine induced the formation of stomatocytes. Experiments performed on IUM at 37 degrees C by fluorescence spectroscopy showed that procaine interacted with the phospholipid bilayer polar groups but not with the hydrophobic acyl chains. X-ray diffraction indicated that procaine perturbed DMPC structure to a higher extent when compared with DMPE, its polar head region being more affected. Electrophysiological measurements disclosed a significant decrease in the potential difference (PD) and in the short-circuit current (Isc) after the application of procaine to isolated toad skin, reflecting inhibition of active ion transport.
authors.affiliation: Faculty of Chemical Sciences, University of Concepcion, Casilla 160-C, Concepción, Chile. msuwalsk@udec.cl
authors.forename: Mario
authors.initials: M
authors.lastname: Suwalsky
authors.forename: Carlos
authors.initials: C
authors.lastname: Schneider
authors.forename: Fernando
authors.initials: F
authors.lastname: Villena
authors.forename: Beryl
authors.initials: B
authors.lastname: Norris
authors.forename: Hernán
authors.initials: H
authors.lastname: Cárdenas
authors.forename: Francisco
authors.initials: F
authors.lastname: Cuevas
authors.forename: Carlos P
authors.initials: CP
authors.lastname: Sotomayor
mesh_terms: D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D001001:Anura; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects*; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D004594:Electrophysiology; D004912:Erythrocytes / Q000187:drug effects* / Q000648:ultrastructure; D005260:Female; D006801:Humans; D017136:Ion Transport / Q000187:drug effects; D008297:Male; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D010714:Phosphatidylethanolamines / Q000737:chemistry; D011343:Procaine / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects* / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D014961:X-Ray Diffraction
chemical_list: D000779:Anesthetics, Local; D008567:Membranes, Artificial; D010714:Phosphatidylethanolamines; D011343:Procaine; D012964:Sodium; D004134:Dimyristoylphosphatidylcholine; C018525:1,2-dimyristoylphosphatidylethanolamine