title: Effects of extremely low frequency electromagnetic fields on membrane-associated enzymes.
abstract: The effects of extremely low frequency electromagnetic fields of 75 Hz were studied on different membrane-associated enzymes. Only the activities of three enzymes out of seven exposed to the field decreased approximately of about 54-61% with field amplitudes above a threshold of 73-151 microT depending on the enzyme. The same field had no effect on the activities of either integral membrane enzymes such as Ca,ATPase, Na/K,ATPase, and succinic dehydrogenase or peripheral membrane enzymes such as photoreceptor PDE. The decrease in enzymatic activity of the field-sensitive enzymes was independent of the time of permanence in the field and was completely reversible. When these enzymes were solubilized with Triton, no effect of the field was obtained on the enzymatic activity, suggesting the crucial role of the membrane in determining the conditions for enzyme inactivation. The role of the particular linkage of the field-sensitive enzymes to the membranes is also discussed.
authors.affiliation: Department of DIBISAA, University of Genoa, viale Benedetto XV, 3 Genova 16131, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Morelli
authors.forename: S
authors.initials: S
authors.lastname: Ravera
authors.forename: I
authors.initials: I
authors.lastname: Panfoli
authors.forename: I M
authors.initials: IM
authors.lastname: Pepe
mesh_terms: D002462:Cell Membrane / Q000737:chemistry* / Q000528:radiation effects*; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D004789:Enzyme Activation / Q000528:radiation effects; D004795:Enzyme Stability / Q000528:radiation effects; D004798:Enzymes / Q000737:chemistry* / Q000528:radiation effects*; D004910:Erythrocyte Membrane / Q000737:chemistry / Q000528:radiation effects; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry* / Q000528:radiation effects*; D011829:Radiation Dosage; D013574:Synaptosomes / Q000737:chemistry / Q000528:radiation effects
chemical_list: D004798:Enzymes; D008565:Membrane Proteins