title: Negative chronotropic effect of botulinum toxin on neonatal rat cardiac myocytes.
abstract: We demonstrated that botulinum neurotoxin attenuated the spontaneous beating rate of cultured cardiac myocytes. Primary cultured cardiac myocytes were prepared from the ventricles of neonatal Wistar rats (1-3 days old). On 7 days after cell seeding, botulinum toxin type A incorporated into liposomes was added to the culture medium. At a final concentration of 5.0 micrograms/ml, botulinum toxin markedly attenuated the beating rate of cardiac myocytes within 2-4 hours. These results demonstrated the effect of SNARE-complex proteins on the spontaneous beating of cardiac myocytes.
authors.affiliation: Department of Microbiology, School of Medicine, Sapporo Medical University, Japan. kimura@sapmed.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Kimura
authors.forename: H
authors.initials: H
authors.lastname: Kimura
authors.forename: N
authors.initials: N
authors.lastname: Yokosawa
authors.forename: H
authors.initials: H
authors.lastname: Isogai
authors.forename: E
authors.initials: E
authors.lastname: Isogai
authors.forename: S
authors.initials: S
authors.lastname: Kozaki
authors.forename: A
authors.initials: A
authors.lastname: Miyamoto
authors.forename: T
authors.initials: T
authors.lastname: Nishikawa
authors.forename: H
authors.initials: H
authors.lastname: Ohshika
authors.forename: T
authors.initials: T
authors.lastname: Kubota
authors.forename: N
authors.initials: N
authors.lastname: Fujii
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D019274:Botulinum Toxins, Type A / Q000037:antagonists & inhibitors / Q000276:immunology / Q000494:pharmacology*; D002411:Cation Exchange Resins / Q000494:pharmacology; D002478:Cells, Cultured; D003864:Depression, Chemical; D006339:Heart Rate / Q000187:drug effects / Q000276:immunology; D008055:Lipids / Q000494:pharmacology; D009200:Myocardial Contraction / Q000187:drug effects* / Q000276:immunology; D009206:Myocardium / Q000166:cytology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000911:Antibodies, Monoclonal; D002411:Cation Exchange Resins; D008055:Lipids; C086724:Lipofectamine; D019274:Botulinum Toxins, Type A