Cardioactive peptides isolated from the brain of a Japanese octopus, Octopus minor.
Octopus cardioactive peptides (Ocp-1: Gly-D-Phe-Gly-Asp, and Ocp-3: Gly-Ser-Trp-Asp) were isolated from brain extracts of the octopus, Octopus minor, using the isolated systemic heart as a bioassay. These peptides showed both positive chronotropic and inotropic effects on the heart. The stereoisomers at position 2 were also isolated, but their activities were only 1/10(3)-1/10(4) those of the corresponding isomers. The presence of the peptides in the systemic heart was confirmed by time-of-flight mass spectrometry (MS) and tandem MS analysis. The results suggested that Ocp-1 and Ocp-3 might be involved in excitatory control of the octopus cardiovascular system as neuropeptides and/or neurohormones.
Iwakoshi
E
E
Suntory Institute for Bioorganic Research, 618-8503, Osaka, Japan.
Hisada
M
M
Minakata
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D006321:Heart / Q000187:drug effects*; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D049831:Octopodiformes; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D010455:Peptides