title: Role of synaptophysin in exocytotic release of dopamine from Xenopus oocytes injected with rat brain mRNA.
abstract: 1. The role of synaptophysin in the exocytotic release of dopamine (DA) was examined in Xenopus laevis oocytes injected with rat brain mRNA. 2. The mRNA-injected oocytes showed DA uptake which depended on the incubation time and external DA concentrations. 3. Stimulation with KCl (10-50 mM) of mRNA-injected oocytes preloaded with DA evoked external Ca2+ -dependent release of DA. The noninjected and water-injected oocytes did not produce uptake of DA and stimulation-evoked release of DA. 4. The high-KCl (50 mM)-stimulated release of DA decreased in the oocytes injected with rat brain mRNA together with antibody to synaptophysin. 5. Immunoblot analysis demonstrated that synaptophysin was expressed in the brain mRNA-injected oocytes but not in the noninjected and water-injected oocytes. 6. Thus, uptake and release machinery similar to native dopaminergic nerve terminals was expressed in Xenopus oocytes by injecting mRNA-extracted from the rat brain, and synaptophysin may play a role in the exocytotic release of DA.
authors.affiliation: Department of Pharmacology, Nagasaki University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shibaguchi
authors.forename: K
authors.initials: K
authors.lastname: Takemura
authors.forename: S
authors.initials: S
authors.lastname: Kan
authors.forename: Y
authors.initials: Y
authors.lastname: Kataoka
authors.forename: M
authors.initials: M
authors.lastname: Kaibara
authors.forename: N
authors.initials: N
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Taniyama
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects / Q000502:physiology; D001923:Brain Chemistry / Q000235:genetics*; D004298:Dopamine / Q000493:pharmacokinetics*; D005089:Exocytosis / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009865:Oocytes / Q000378:metabolism; D011189:Potassium Chloride / Q000494:pharmacology; D012333:RNA, Messenger / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D016708:Synaptophysin / Q000276:immunology / Q000378:metabolism*; D014316:Tritium; D014982:Xenopus laevis
chemical_list: D000906:Antibodies; D012333:RNA, Messenger; D016708:Synaptophysin; D014316:Tritium; D015102:3,4-Dihydroxyphenylacetic Acid; D011189:Potassium Chloride; D004298:Dopamine