title: Discontinuous volume transitions induced by calcium-sodium ion exchange in anionic gels and their neurobiological implications.
abstract: Discontinuous volume transitions in poly (acrylic acid) gels were studied by determining equilibrium swelling curves of small gel beads immersed in salt solutions containing varying concentrations of Ca2+ and Na+. Reversible contractions of gel membranes associated with Ca(2+)-Na+ exchange were examined using both isometric and isotonic recording devices. A discontinuous change in electric conductance was demonstrated in association with Ca(2+)-Na+ exchange in gel membranes. These experimental findings provide a sound physicochemical basis for elucidating the mechanism of nerve excitation.
authors.affiliation: Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, Maryland 20892.
authors.forename: I
authors.initials: I
authors.lastname: Tasaki
authors.forename: P M
authors.initials: PM
authors.lastname: Byrne
mesh_terms: D000200:Action Potentials; D000838:Anions / Q000737:chemistry; D002118:Calcium / Q000737:chemistry* / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D004553:Electric Conductivity; D005782:Gels / Q000737:chemistry*; D007700:Kinetics; D008954:Models, Biological; D009412:Nerve Fibers / Q000502:physiology*; D012964:Sodium / Q000737:chemistry* / Q000378:metabolism*; D019831:Sodium-Calcium Exchanger; D012996:Solutions
chemical_list: D000838:Anions; D002352:Carrier Proteins; D005782:Gels; D019831:Sodium-Calcium Exchanger; D012996:Solutions; D012964:Sodium; D002118:Calcium