title: NGIWYamide-induced contraction of tube feet and distribution of NGIWYamide-like immunoreactivity in nerves of the starfish Asterina pectinifera.
abstract: NGIWYamide, a neuropeptide recently isolated from sea cucumbers, was tested on tube feet of the starfish Asterina pectinifera. NGIWYamide (10(-6)-10(-4) M) caused contraction of isolated tube feet. NGIWYamide-like immunoreactivity (NGIWYa-LI) was investigated with an antiserum against NGIWYamide. NGIWYa-LI was found in the radial nerve cord (RNC), the marginal nerve, and the tube feet. Both ectoneural and hyponeural parts of the RNC showed NGIWYa-LI. Immunoreactive cell bodies were found in both parts of RNC. Extensive labeling in the basal region of the ectoneural part suggests that a substantial proportion of axons in this part contains NGIWYamide or a similar substance. In tube feet, NGIWYa-LI was found in the sub-epithelial nerve plexus and in the basal nerve ring. Double labeling along with 1E11, a neuron-specific monoclonal antibody developed from A. pectinifera, indicated that the structures with NGIWYa-LI are neurons. These results suggest that NGIWYamide or an NGIWYamide-like peptide exists in starfish and functions as a neurotransmitter or a neuromodulator.
authors.affiliation: Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, O-okayama, Tokyo, Japan. apurbaksaha@yahoo.com
authors.forename: Apurba Kumar
authors.initials: AK
authors.lastname: Saha
authors.forename: Masaki
authors.initials: M
authors.lastname: Tamori
authors.forename: Masahide
authors.initials: M
authors.lastname: Inoue
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nakajima
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Motokawa
mesh_terms: D000818:Animals; D047288:Asterina / Q000378:metabolism / Q000502:physiology*; D017952:Ganglia, Invertebrate / Q000502:physiology*; D007150:Immunohistochemistry / Q000662:veterinary; D008124:Locomotion / Q000502:physiology*; D009479:Neuropeptides / Q000378:metabolism / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism / Q000502:physiology
chemical_list: D009479:Neuropeptides; D018377:Neurotransmitter Agents; C113892:asparaginyl-glycyl-isoleucyl-tryptophyl-tyrosinamide