title: Modulation of the cardiac membrane-bound cyclic nucleotide phosphodiesterase: inhibition due to a contamination of TLC purified S-adenosyl-L-[methyl-3H] methionine by Zn++ ions.
abstract: Cardiac membranes pretreated with S-Adenosyl-L-[methyl-3H] methionine([3H] SAM) purified on TLC silica gel 60 F254 plates exhibited a marked decrease in cyclic AMP and cyclic GMP phosphodiesterase activity. However, this inhibition did not appear when membranes were incubated with either [14C] SAM or unlabelled SAM. We showed that, during the TLC purification of [3H] SAM, which involved an acidic elution step, minute amounts of the fluorescent indicator F254 (Zn sulfur) were eluted. The contaminating Zn++ ions strongly inhibited cyclic nucleotide phosphodiesterase activity and phospholipid methylation with I50 values in the micromolar range.
authors.forename: M
authors.initials: M
authors.lastname: Dubois
authors.forename: A F
authors.initials: AF
authors.lastname: Prigent
authors.forename: G
authors.initials: G
authors.lastname: Némoz
authors.forename: S
authors.initials: S
authors.lastname: Fougier
authors.forename: H
authors.initials: H
authors.lastname: Pacheco
mesh_terms: D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000037:antagonists & inhibitors*; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D002855:Chromatography, Thin Layer; D005453:Fluorescence; D066298:In Vitro Techniques; D008297:Male; D008745:Methylation; D009206:Myocardium / Q000201:enzymology*; D010743:Phospholipids / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012436:S-Adenosylmethionine / Q000494:pharmacology*; D015032:Zinc / Q000494:pharmacology*
chemical_list: D010743:Phospholipids; D012436:S-Adenosylmethionine; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases; D015032:Zinc