title: Seasonal Changes in the Tetrodotoxin Content of the Flatworm Planocera multitentaculata.
abstract: Tetrodotoxin (TTX) is a potent neurotoxin that acts specifically on voltage-gated sodium channels on excitable membranes of muscle and nerve tissues. The biosynthetic process for TTX is unclear, although marine bacteria are generally thought to be the primary producers. The marine flatwormPlanocera multitentaculatais a known TTX-bearing organism, and is suspected to be a TTX supplier to pufferfish. In this study, flatworm specimens were collected from an intertidal zone in Hayama, Kanagawa, Japan, the TTX content of the flatworm was measured using liquid chromatography with tandem mass spectrometry (LC-MS/MS), and seasonal changes in TTX content were investigated. No significant difference in TTX concentration of the flatworm body was found between the spawning period and other periods. However, the TTX content in individual flatworms was significantly higher in the spawning period than at other times. The TTX content rose in association with an increase in the body weight of the flatworm.
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. rikopin.0202@gmail.com.
authors.forename: Riko
authors.initials: R
authors.lastname: Yamada
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. t007_moyasi@yahoo.co.jp.
authors.forename: Tadasuke
authors.initials: T
authors.lastname: Tsunashima
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. mitsuki.takei.nubs@gmail.com.
authors.forename: Mitsuki
authors.initials: M
authors.lastname: Takei
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. tatsunorisato.nubs@gmail.com.
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Sato
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. wajimayoshi.nu@gmail.com.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Wajima
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. brma13039@g.nihon-u.ac.jp.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawase
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. n.u.oshikirishotaro@gmail.com.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Oshikiri
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. himajin0090@gmail.com.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kajitani
authors.affiliation: The Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Minato, Tokyo 108-8477, Japan. keita.kosoba@gmail.com.
authors.forename: Keita
authors.initials: K
authors.lastname: Kosoba
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. ueda.h.65039@gmail.com.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ueda
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. abe.kouko@nihon-u.ac.jp.
authors.forename: Koko
authors.initials: K
authors.lastname: Abe
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. sitoi@nihon-u.ac.jp.
authors.forename: Shiro
authors.initials: S
authors.lastname: Itoi
authors.affiliation: Department of Marine Science and Resources, Nihon University, Fujisawa, Kanagawa 252-0880, Japan. sugita.haruo@nihon-u.ac.jp.
authors.forename: Haruo
authors.initials: H
authors.lastname: Sugita
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods; D007564:Japan; D010986:Platyhelminths / Q000378:metabolism*; D012621:Seasons; D053719:Tandem Mass Spectrometry / Q000379:methods; D023721:Tetraodontiformes / Q000378:metabolism; D013779:Tetrodotoxin / Q000378:metabolism*
chemical_list: D013779:Tetrodotoxin
keywords: Planocera multitentaculata; flatworm; planocerid; pufferfish; tetrodotoxin (TTX)