[Effect of gold (III) on prostaglandin E2-stimulated adenyl cyclase in chick fibroblasts and osteoblasts].
Gold (III) (Au(III) up to 0.25 microM increased prostaglandin E2-sensitive chick osteoblast and fibroblast adenylate cyclase activity without affecting 5'-guanylylimidodiphosphate-stimulated enzyme activity. Au (III) at 5-50 microM inhibited hormone- and nucleotide-mediated activation of adenylate cyclase. This process is time-dependent, irreversible and can not be explained by desensitivation of the PGE2-receptor. Basal adenylate cyclase activity was not influenced by Au (III) in the given concentrations. Pretreatment of membranes with 5'-guanylylimidodiphosphate prior to incubation with Au (III) prevented the inhibitory effect of Au (III) on adenylate cyclase, similar to the incubation experiments with NEM instead of Au (III). Our data suggest that Au (III) at low concentrations unspecifically stimulates PGE2-sensitive adenylate cyclase by binding to sulfhydryl groups of the receptor protein and that Au (III) at high concentrations specifically inhibits PGE2-sensitive adenylate cyclase by binding to sulfhydryl groups of the N-Protein and/or of the catalytic unit.
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D004789:Enzyme Activation / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects*; D006046:Gold / Q000494:pharmacology*; D017612:Gold Compounds; D010006:Osteoblasts / Q000187:drug effects*; D011458:Prostaglandins E / Q000494:pharmacology*
D017612:Gold Compounds; D011458:Prostaglandins E; C038016:gold chloride; D006046:Gold; D000262:Adenylyl Cyclases
Gold(III)-Wirkung auf die durch Prostaglandin E2 stimulierte Adenylcyclase in Kückenfibroblasten und -osteoblasten.